diff --git a/driver/driver.go b/driver/driver.go
index 5a8222f70..d5860036c 100644
--- a/driver/driver.go
+++ b/driver/driver.go
@@ -186,9 +186,10 @@ type ObjFile interface {
 
 // A Frame describes a single line in a source file.
 type Frame struct {
-	Func string // name of function
-	File string // source file name
-	Line int    // line in file
+	Func   string // name of function
+	File   string // source file name
+	Line   int    // line in file
+	Column int    // column in file
 }
 
 // A Sym describes a single symbol in an object file.
diff --git a/internal/binutils/addr2liner_llvm.go b/internal/binutils/addr2liner_llvm.go
index 491422fcd..3049545b6 100644
--- a/internal/binutils/addr2liner_llvm.go
+++ b/internal/binutils/addr2liner_llvm.go
@@ -129,6 +129,7 @@ func (d *llvmSymbolizer) readFrame() (plugin.Frame, bool) {
 	}
 
 	linenumber := 0
+	columnnumber := 0
 	// The llvm-symbolizer outputs the <file_name>:<line_number>:<column_number>.
 	// When it cannot identify the source code location, it outputs "??:0:0".
 	// Older versions output just the filename and line number, so we check for
@@ -137,22 +138,27 @@ func (d *llvmSymbolizer) readFrame() (plugin.Frame, bool) {
 		fileline = ""
 	} else {
 		switch split := strings.Split(fileline, ":"); len(split) {
-		case 1:
-			// filename
-			fileline = split[0]
-		case 2, 3:
-			// filename:line , or
-			// filename:line:disc , or
-			fileline = split[0]
+		case 3:
+			// filename:line:column
+			if col, err := strconv.Atoi(split[2]); err == nil {
+				columnnumber = col
+			}
+			fallthrough
+		case 2:
+			// filename:line
 			if line, err := strconv.Atoi(split[1]); err == nil {
 				linenumber = line
 			}
+			fallthrough
+		case 1:
+			// filename
+			fileline = split[0]
 		default:
 			// Unrecognized, ignore
 		}
 	}
 
-	return plugin.Frame{Func: funcname, File: fileline, Line: linenumber}, false
+	return plugin.Frame{Func: funcname, File: fileline, Line: linenumber, Column: columnnumber}, false
 }
 
 // addrInfo returns the stack frame information for a specific program
diff --git a/internal/binutils/binutils_test.go b/internal/binutils/binutils_test.go
index b45fe9842..dd931f4b5 100644
--- a/internal/binutils/binutils_test.go
+++ b/internal/binutils/binutils_test.go
@@ -461,8 +461,8 @@ func TestLLVMSymbolizer(t *testing.T) {
 		frames []plugin.Frame
 	}{
 		{0x10, false, []plugin.Frame{
-			{Func: "Inlined_0x10", File: "foo.h", Line: 0},
-			{Func: "Func_0x10", File: "foo.c", Line: 2},
+			{Func: "Inlined_0x10", File: "foo.h", Line: 0, Column: 0},
+			{Func: "Func_0x10", File: "foo.c", Line: 2, Column: 1},
 		}},
 		{0x20, true, []plugin.Frame{
 			{Func: "foo_0x20", File: "0x20 8"},
@@ -532,7 +532,7 @@ func TestPEFile(t *testing.T) {
 				t.Fatalf("SourceLine: unexpected error %v", err)
 			}
 			wantFrames := []plugin.Frame{
-				{Func: "main", File: "hello.c", Line: 3},
+				{Func: "main", File: "hello.c", Line: 3, Column: 12},
 			}
 			if !reflect.DeepEqual(gotFrames, wantFrames) {
 				t.Fatalf("SourceLine for main: got %v; want %v\n", gotFrames, wantFrames)
diff --git a/internal/driver/commands.go b/internal/driver/commands.go
index c9edf10bb..f990780d7 100644
--- a/internal/driver/commands.go
+++ b/internal/driver/commands.go
@@ -247,6 +247,8 @@ var configHelp = map[string]string{
 	"noinlines": helpText(
 		"Ignore inlines.",
 		"Attributes inlined functions to their first out-of-line caller."),
+	"showcolumns": helpText(
+		"Show column numbers at the source code line level."),
 }
 
 func helpText(s ...string) string {
diff --git a/internal/driver/config.go b/internal/driver/config.go
index 9fcdd459b..f7d227416 100644
--- a/internal/driver/config.go
+++ b/internal/driver/config.go
@@ -51,6 +51,7 @@ type config struct {
 	TagShow      string  `json:"tagshow,omitempty"`
 	TagHide      string  `json:"taghide,omitempty"`
 	NoInlines    bool    `json:"noinlines,omitempty"`
+	ShowColumns  bool    `json:"showcolumns,omitempty"`
 
 	// Output granularity
 	Granularity string `json:"granularity,omitempty"`
@@ -157,6 +158,7 @@ func init() {
 		"sort":                 "sort",
 		"granularity":          "g",
 		"noinlines":            "noinlines",
+		"showcolumns":          "showcolumns",
 	}
 
 	def := defaultConfig()
diff --git a/internal/driver/driver.go b/internal/driver/driver.go
index 27681c540..74ce8cb42 100644
--- a/internal/driver/driver.go
+++ b/internal/driver/driver.go
@@ -256,7 +256,7 @@ func aggregate(prof *profile.Profile, cfg config) error {
 	default:
 		return fmt.Errorf("unexpected granularity")
 	}
-	return prof.Aggregate(inlines, function, filename, linenumber, address)
+	return prof.Aggregate(inlines, function, filename, linenumber, cfg.ShowColumns, address)
 }
 
 func reportOptions(p *profile.Profile, numLabelUnits map[string]string, cfg config) (*report.Options, error) {
diff --git a/internal/driver/driver_test.go b/internal/driver/driver_test.go
index abe3597eb..bc7a97eb7 100644
--- a/internal/driver/driver_test.go
+++ b/internal/driver/driver_test.go
@@ -1680,8 +1680,9 @@ func (m *mockFile) BuildID() string {
 func (*mockFile) SourceLine(addr uint64) ([]plugin.Frame, error) {
 	// Return enough data to support the SourceLine() calls needed for
 	// weblist on cpuProfile() contents.
-	frame := func(fn, file string, line int) plugin.Frame {
-		return plugin.Frame{Func: fn, File: file, Line: line}
+	frame := func(fn, file string, num int) plugin.Frame {
+		// Reuse the same num for line number and column number.
+		return plugin.Frame{Func: fn, File: file, Line: num, Column: num}
 	}
 	switch addr {
 	case 0x1000:
diff --git a/internal/driver/settings_test.go b/internal/driver/settings_test.go
index 7d3aad9a0..07bf6acb4 100644
--- a/internal/driver/settings_test.go
+++ b/internal/driver/settings_test.go
@@ -86,6 +86,7 @@ func TestParseConfig(t *testing.T) {
 		Sort:                "cum",
 		Granularity:         "functions",
 		NoInlines:           true,
+		ShowColumns:         true,
 	}
 	url, changed := cfg.makeURL(url.URL{})
 	if !changed {
diff --git a/internal/graph/graph.go b/internal/graph/graph.go
index b64ef2799..5ad10a2ae 100644
--- a/internal/graph/graph.go
+++ b/internal/graph/graph.go
@@ -154,6 +154,7 @@ type NodeInfo struct {
 	Address           uint64
 	File              string
 	StartLine, Lineno int
+	Columnno          int
 	Objfile           string
 }
 
@@ -174,8 +175,12 @@ func (i *NodeInfo) NameComponents() []string {
 
 	switch {
 	case i.Lineno != 0:
+		s := fmt.Sprintf("%s:%d", i.File, i.Lineno)
+		if i.Columnno != 0 {
+			s += fmt.Sprintf(":%d", i.Columnno)
+		}
 		// User requested line numbers, provide what we have.
-		name = append(name, fmt.Sprintf("%s:%d", i.File, i.Lineno))
+		name = append(name, s)
 	case i.File != "":
 		// User requested file name, provide it.
 		name = append(name, i.File)
@@ -239,6 +244,7 @@ func (nm NodeMap) FindOrInsertNode(info NodeInfo, kept NodeSet) *Node {
 	// Find a node that represents the whole function.
 	info.Address = 0
 	info.Lineno = 0
+	info.Columnno = 0
 	n.Function = nm.FindOrInsertNode(info, nil)
 	return n
 }
@@ -592,9 +598,10 @@ func nodeInfo(l *profile.Location, line profile.Line, objfile string, o *Options
 		return &NodeInfo{Address: l.Address, Objfile: objfile}
 	}
 	ni := &NodeInfo{
-		Address: l.Address,
-		Lineno:  int(line.Line),
-		Name:    line.Function.Name,
+		Address:  l.Address,
+		Lineno:   int(line.Line),
+		Columnno: int(line.Column),
+		Name:     line.Function.Name,
 	}
 	if fname := line.Function.Filename; fname != "" {
 		ni.File = filepath.Clean(fname)
diff --git a/internal/plugin/plugin.go b/internal/plugin/plugin.go
index 98eb1dd81..c93455103 100644
--- a/internal/plugin/plugin.go
+++ b/internal/plugin/plugin.go
@@ -157,11 +157,12 @@ type ObjFile interface {
 	Close() error
 }
 
-// A Frame describes a single line in a source file.
+// A Frame describes a location in a single line in a source file.
 type Frame struct {
-	Func string // name of function
-	File string // source file name
-	Line int    // line in file
+	Func   string // name of function
+	File   string // source file name
+	Line   int    // line in file
+	Column int    // column in line (if available)
 }
 
 // A Sym describes a single symbol in an object file.
diff --git a/internal/report/report.go b/internal/report/report.go
index f73e49a17..47e514449 100644
--- a/internal/report/report.go
+++ b/internal/report/report.go
@@ -339,6 +339,7 @@ func printTopProto(w io.Writer, rpt *Report) error {
 			Line: []profile.Line{
 				{
 					Line:     int64(n.Info.Lineno),
+					Column:   int64(n.Info.Columnno),
 					Function: f,
 				},
 			},
diff --git a/internal/report/report_test.go b/internal/report/report_test.go
index eb13e7c18..bc0b5dc1b 100644
--- a/internal/report/report_test.go
+++ b/internal/report/report_test.go
@@ -191,6 +191,7 @@ var testL = []*profile.Location{
 			{
 				Function: testF[0],
 				Line:     2,
+				Column:   2,
 			},
 		},
 	},
@@ -201,6 +202,7 @@ var testL = []*profile.Location{
 			{
 				Function: testF[1],
 				Line:     4,
+				Column:   4,
 			},
 		},
 	},
diff --git a/internal/report/testdata/source.dot b/internal/report/testdata/source.dot
index e0dadb1bc..83ee42e91 100644
--- a/internal/report/testdata/source.dot
+++ b/internal/report/testdata/source.dot
@@ -2,16 +2,16 @@ digraph "unnamed" {
 node [style=filled fillcolor="#f8f8f8"]
 subgraph cluster_L { "Duration: 10s, Total samples = 11111 " [shape=box fontsize=16 label="Duration: 10s, Total samples = 11111 \lShowing nodes accounting for 11111, 100% of 11111 total\l\lSee https://git.io/JfYMW for how to read the graph\l"] }
 N1 [label="tee\nsource2:8\n10000 (90.00%)" id="node1" fontsize=24 shape=box tooltip="tee testdata/source2:8 (10000)" color="#b20500" fillcolor="#edd6d5"]
-N2 [label="main\nsource1:2\n1 (0.009%)\nof 11111 (100%)" id="node2" fontsize=9 shape=box tooltip="main testdata/source1:2 (11111)" color="#b20000" fillcolor="#edd5d5"]
+N2 [label="main\nsource1:2:2\n1 (0.009%)\nof 11111 (100%)" id="node2" fontsize=9 shape=box tooltip="main testdata/source1:2:2 (11111)" color="#b20000" fillcolor="#edd5d5"]
 N3 [label="tee\nsource2:2\n1000 (9.00%)\nof 11000 (99.00%)" id="node3" fontsize=14 shape=box tooltip="tee testdata/source2:2 (11000)" color="#b20000" fillcolor="#edd5d5"]
 N4 [label="tee\nsource2:8\n100 (0.9%)" id="node4" fontsize=10 shape=box tooltip="tee testdata/source2:8 (100)" color="#b2b0aa" fillcolor="#edecec"]
 N5 [label="bar\nsource1:10\n10 (0.09%)" id="node5" fontsize=9 shape=box tooltip="bar testdata/source1:10 (10)" color="#b2b2b1" fillcolor="#ededed"]
 N6 [label="bar\nsource1:10\n0 of 100 (0.9%)" id="node6" fontsize=8 shape=box tooltip="bar testdata/source1:10 (100)" color="#b2b0aa" fillcolor="#edecec"]
-N7 [label="foo\nsource1:4\n0 of 10 (0.09%)" id="node7" fontsize=8 shape=box tooltip="foo testdata/source1:4 (10)" color="#b2b2b1" fillcolor="#ededed"]
-N2 -> N3 [label=" 11000" weight=100 penwidth=5 color="#b20000" tooltip="main testdata/source1:2 -> tee testdata/source2:2 (11000)" labeltooltip="main testdata/source1:2 -> tee testdata/source2:2 (11000)"]
+N7 [label="foo\nsource1:4:4\n0 of 10 (0.09%)" id="node7" fontsize=8 shape=box tooltip="foo testdata/source1:4:4 (10)" color="#b2b2b1" fillcolor="#ededed"]
+N2 -> N3 [label=" 11000" weight=100 penwidth=5 color="#b20000" tooltip="main testdata/source1:2:2 -> tee testdata/source2:2 (11000)" labeltooltip="main testdata/source1:2:2 -> tee testdata/source2:2 (11000)"]
 N3 -> N1 [label=" 10000" weight=91 penwidth=5 color="#b20500" tooltip="tee testdata/source2:2 -> tee testdata/source2:8 (10000)" labeltooltip="tee testdata/source2:2 -> tee testdata/source2:8 (10000)"]
 N6 -> N4 [label=" 100" color="#b2b0aa" tooltip="bar testdata/source1:10 -> tee testdata/source2:8 (100)" labeltooltip="bar testdata/source1:10 -> tee testdata/source2:8 (100)"]
-N2 -> N6 [label=" 100" color="#b2b0aa" tooltip="main testdata/source1:2 -> bar testdata/source1:10 (100)" labeltooltip="main testdata/source1:2 -> bar testdata/source1:10 (100)"]
-N7 -> N5 [label=" 10" color="#b2b2b1" tooltip="foo testdata/source1:4 -> bar testdata/source1:10 (10)" labeltooltip="foo testdata/source1:4 -> bar testdata/source1:10 (10)"]
-N2 -> N7 [label=" 10" color="#b2b2b1" tooltip="main testdata/source1:2 -> foo testdata/source1:4 (10)" labeltooltip="main testdata/source1:2 -> foo testdata/source1:4 (10)"]
+N2 -> N6 [label=" 100" color="#b2b0aa" tooltip="main testdata/source1:2:2 -> bar testdata/source1:10 (100)" labeltooltip="main testdata/source1:2:2 -> bar testdata/source1:10 (100)"]
+N7 -> N5 [label=" 10" color="#b2b2b1" tooltip="foo testdata/source1:4:4 -> bar testdata/source1:10 (10)" labeltooltip="foo testdata/source1:4:4 -> bar testdata/source1:10 (10)"]
+N2 -> N7 [label=" 10" color="#b2b2b1" tooltip="main testdata/source1:2:2 -> foo testdata/source1:4:4 (10)" labeltooltip="main testdata/source1:2:2 -> foo testdata/source1:4:4 (10)"]
 }
diff --git a/internal/symbolizer/symbolizer.go b/internal/symbolizer/symbolizer.go
index c3f6cc628..5ca71ab8b 100644
--- a/internal/symbolizer/symbolizer.go
+++ b/internal/symbolizer/symbolizer.go
@@ -181,6 +181,7 @@ func doLocalSymbolize(prof *profile.Profile, fast, force bool, obj plugin.ObjToo
 			l.Line[i] = profile.Line{
 				Function: f,
 				Line:     int64(frame.Line),
+				Column:   int64(frame.Column),
 			}
 		}
 
diff --git a/internal/symbolizer/symbolizer_test.go b/internal/symbolizer/symbolizer_test.go
index adb5f835a..35134ef11 100644
--- a/internal/symbolizer/symbolizer_test.go
+++ b/internal/symbolizer/symbolizer_test.go
@@ -242,23 +242,27 @@ func checkSymbolizedLocation(a uint64, got []profile.Line) error {
 		if g.Line != int64(w.Line) {
 			return fmt.Errorf("want lineno: %d, got %d", w.Line, g.Line)
 		}
+		if g.Column != int64(w.Column) {
+			return fmt.Errorf("want columnno: %d, got %d", w.Column, g.Column)
+		}
 	}
 	return nil
 }
 
 var mockAddresses = map[uint64][]plugin.Frame{
-	1000: {frame("fun11", "file11.src", 10)},
-	2000: {frame("fun21", "file21.src", 20), frame("fun22", "file22.src", 20)},
-	3000: {frame("fun31", "file31.src", 30), frame("fun32", "file32.src", 30), frame("fun33", "file33.src", 30)},
-	4000: {frame("fun41", "file41.src", 40), frame("fun42", "file42.src", 40), frame("fun43", "file43.src", 40), frame("fun44", "file44.src", 40)},
-	5000: {frame("fun51", "file51.src", 50), frame("fun52", "file52.src", 50), frame("fun53", "file53.src", 50), frame("fun54", "file54.src", 50), frame("fun55", "file55.src", 50)},
+	1000: {frame("fun11", "file11.src", 10, 1)},
+	2000: {frame("fun21", "file21.src", 20, 2), frame("fun22", "file22.src", 20, 2)},
+	3000: {frame("fun31", "file31.src", 30, 3), frame("fun32", "file32.src", 30, 3), frame("fun33", "file33.src", 30, 3)},
+	4000: {frame("fun41", "file41.src", 40, 4), frame("fun42", "file42.src", 40, 4), frame("fun43", "file43.src", 40, 4), frame("fun44", "file44.src", 40, 4)},
+	5000: {frame("fun51", "file51.src", 50, 5), frame("fun52", "file52.src", 50, 5), frame("fun53", "file53.src", 50, 5), frame("fun54", "file54.src", 50, 5), frame("fun55", "file55.src", 50, 5)},
 }
 
-func frame(fname, file string, line int) plugin.Frame {
+func frame(fname, file string, line int, column int) plugin.Frame {
 	return plugin.Frame{
-		Func: fname,
-		File: file,
-		Line: line}
+		Func:   fname,
+		File:   file,
+		Line:   line,
+		Column: column}
 }
 
 func TestDemangleSingleFunction(t *testing.T) {
diff --git a/profile/encode.go b/profile/encode.go
index 182c926b9..860bb304c 100644
--- a/profile/encode.go
+++ b/profile/encode.go
@@ -530,6 +530,7 @@ func (p *Line) decoder() []decoder {
 func (p *Line) encode(b *buffer) {
 	encodeUint64Opt(b, 1, p.functionIDX)
 	encodeInt64Opt(b, 2, p.Line)
+	encodeInt64Opt(b, 3, p.Column)
 }
 
 var lineDecoder = []decoder{
@@ -538,6 +539,8 @@ var lineDecoder = []decoder{
 	func(b *buffer, m message) error { return decodeUint64(b, &m.(*Line).functionIDX) },
 	// optional int64 line = 2
 	func(b *buffer, m message) error { return decodeInt64(b, &m.(*Line).Line) },
+	// optional int64 column = 3
+	func(b *buffer, m message) error { return decodeInt64(b, &m.(*Line).Column) },
 }
 
 func (p *Function) decoder() []decoder {
diff --git a/profile/legacy_java_profile.go b/profile/legacy_java_profile.go
index 91f45e53c..4580bab18 100644
--- a/profile/legacy_java_profile.go
+++ b/profile/legacy_java_profile.go
@@ -56,7 +56,7 @@ func javaCPUProfile(b []byte, period int64, parse func(b []byte) (uint64, []byte
 	}
 
 	// Strip out addresses for better merge.
-	if err = p.Aggregate(true, true, true, true, false); err != nil {
+	if err = p.Aggregate(true, true, true, true, false, false); err != nil {
 		return nil, err
 	}
 
@@ -99,7 +99,7 @@ func parseJavaProfile(b []byte) (*Profile, error) {
 	}
 
 	// Strip out addresses for better merge.
-	if err = p.Aggregate(true, true, true, true, false); err != nil {
+	if err = p.Aggregate(true, true, true, true, false, false); err != nil {
 		return nil, err
 	}
 
diff --git a/profile/merge.go b/profile/merge.go
index 4b66282cb..eee0132e7 100644
--- a/profile/merge.go
+++ b/profile/merge.go
@@ -326,12 +326,13 @@ func (l *Location) key() locationKey {
 		key.addr -= l.Mapping.Start
 		key.mappingID = l.Mapping.ID
 	}
-	lines := make([]string, len(l.Line)*2)
+	lines := make([]string, len(l.Line)*3)
 	for i, line := range l.Line {
 		if line.Function != nil {
 			lines[i*2] = strconv.FormatUint(line.Function.ID, 16)
 		}
 		lines[i*2+1] = strconv.FormatInt(line.Line, 16)
+		lines[i*2+2] = strconv.FormatInt(line.Column, 16)
 	}
 	key.lines = strings.Join(lines, "|")
 	return key
@@ -418,6 +419,7 @@ func (pm *profileMerger) mapLine(src Line) Line {
 	ln := Line{
 		Function: pm.mapFunction(src.Function),
 		Line:     src.Line,
+		Column:   src.Column,
 	}
 	return ln
 }
diff --git a/profile/profile.go b/profile/profile.go
index 60ef7e926..62df80a55 100644
--- a/profile/profile.go
+++ b/profile/profile.go
@@ -145,6 +145,7 @@ type Location struct {
 type Line struct {
 	Function *Function
 	Line     int64
+	Column   int64
 
 	functionIDX uint64
 }
@@ -436,7 +437,7 @@ func (p *Profile) CheckValid() error {
 // Aggregate merges the locations in the profile into equivalence
 // classes preserving the request attributes. It also updates the
 // samples to point to the merged locations.
-func (p *Profile) Aggregate(inlineFrame, function, filename, linenumber, address bool) error {
+func (p *Profile) Aggregate(inlineFrame, function, filename, linenumber, columnnumber, address bool) error {
 	for _, m := range p.Mapping {
 		m.HasInlineFrames = m.HasInlineFrames && inlineFrame
 		m.HasFunctions = m.HasFunctions && function
@@ -458,7 +459,7 @@ func (p *Profile) Aggregate(inlineFrame, function, filename, linenumber, address
 	}
 
 	// Aggregate locations
-	if !inlineFrame || !address || !linenumber {
+	if !inlineFrame || !address || !linenumber || !columnnumber {
 		for _, l := range p.Location {
 			if !inlineFrame && len(l.Line) > 1 {
 				l.Line = l.Line[len(l.Line)-1:]
@@ -466,6 +467,12 @@ func (p *Profile) Aggregate(inlineFrame, function, filename, linenumber, address
 			if !linenumber {
 				for i := range l.Line {
 					l.Line[i].Line = 0
+					l.Line[i].Column = 0
+				}
+			}
+			if !columnnumber {
+				for i := range l.Line {
+					l.Line[i].Column = 0
 				}
 			}
 			if !address {
@@ -627,10 +634,11 @@ func (l *Location) string() string {
 	for li := range l.Line {
 		lnStr := "??"
 		if fn := l.Line[li].Function; fn != nil {
-			lnStr = fmt.Sprintf("%s %s:%d s=%d",
+			lnStr = fmt.Sprintf("%s %s:%d:%d s=%d",
 				fn.Name,
 				fn.Filename,
 				l.Line[li].Line,
+				l.Line[li].Column,
 				fn.StartLine)
 			if fn.Name != fn.SystemName {
 				lnStr = lnStr + "(" + fn.SystemName + ")"
diff --git a/profile/profile_test.go b/profile/profile_test.go
index 674ced2c7..c9e39a623 100644
--- a/profile/profile_test.go
+++ b/profile/profile_test.go
@@ -274,7 +274,7 @@ var cpuL = []*Location{
 		Mapping: cpuM[1],
 		Address: 0x1000,
 		Line: []Line{
-			{Function: cpuF[0], Line: 1},
+			{Function: cpuF[0], Line: 1, Column: 1},
 		},
 	},
 	{
@@ -282,8 +282,8 @@ var cpuL = []*Location{
 		Mapping: cpuM[0],
 		Address: 0x2000,
 		Line: []Line{
-			{Function: cpuF[1], Line: 2},
-			{Function: cpuF[2], Line: 1},
+			{Function: cpuF[1], Line: 2, Column: 2},
+			{Function: cpuF[2], Line: 1, Column: 1},
 		},
 	},
 	{
@@ -291,8 +291,8 @@ var cpuL = []*Location{
 		Mapping: cpuM[0],
 		Address: 0x3000,
 		Line: []Line{
-			{Function: cpuF[1], Line: 2},
-			{Function: cpuF[2], Line: 1},
+			{Function: cpuF[1], Line: 2, Column: 2},
+			{Function: cpuF[2], Line: 1, Column: 1},
 		},
 	},
 	{
@@ -300,7 +300,7 @@ var cpuL = []*Location{
 		Mapping: cpuM[0],
 		Address: 0x3001,
 		Line: []Line{
-			{Function: cpuF[2], Line: 2},
+			{Function: cpuF[2], Line: 2, Column: 2},
 		},
 	},
 	{
@@ -308,7 +308,16 @@ var cpuL = []*Location{
 		Mapping: cpuM[0],
 		Address: 0x3002,
 		Line: []Line{
-			{Function: cpuF[2], Line: 3},
+			{Function: cpuF[2], Line: 3, Column: 3},
+		},
+	},
+	// Differs from 1000 due to address and column number.
+	{
+		ID:      1001,
+		Mapping: cpuM[1],
+		Address: 0x1001,
+		Line: []Line{
+			{Function: cpuF[0], Line: 1, Column: 2},
 		},
 	},
 }
@@ -564,26 +573,92 @@ var testProfile5 = &Profile{
 	Mapping:  cpuM,
 }
 
+var testProfile6 = &Profile{
+	TimeNanos:     10000,
+	PeriodType:    &ValueType{Type: "cpu", Unit: "milliseconds"},
+	Period:        1,
+	DurationNanos: 10e9,
+	SampleType: []*ValueType{
+		{Type: "samples", Unit: "count"},
+		{Type: "cpu", Unit: "milliseconds"},
+	},
+	Sample: []*Sample{
+		{
+			Location: []*Location{cpuL[0]},
+			Value:    []int64{1000, 1000},
+			Label: map[string][]string{
+				"key1": {"tag1"},
+				"key2": {"tag1"},
+			},
+		},
+		{
+			Location: []*Location{cpuL[1], cpuL[0]},
+			Value:    []int64{100, 100},
+			Label: map[string][]string{
+				"key1": {"tag2"},
+				"key3": {"tag2"},
+			},
+		},
+		{
+			Location: []*Location{cpuL[2], cpuL[0]},
+			Value:    []int64{10, 10},
+			Label: map[string][]string{
+				"key1": {"tag3"},
+				"key2": {"tag2"},
+			},
+		},
+		{
+			Location: []*Location{cpuL[3], cpuL[0]},
+			Value:    []int64{10000, 10000},
+			Label: map[string][]string{
+				"key1": {"tag4"},
+				"key2": {"tag1"},
+			},
+		},
+		{
+			Location: []*Location{cpuL[4], cpuL[0]},
+			Value:    []int64{1, 1},
+			Label: map[string][]string{
+				"key1": {"tag4"},
+				"key2": {"tag1"},
+			},
+		},
+		{
+			Location: []*Location{cpuL[5]},
+			Value:    []int64{1, 1},
+			Label: map[string][]string{
+				"key1": {"tag5"},
+				"key2": {"tag1"},
+			},
+		},
+	},
+	Location: cpuL,
+	Function: cpuF,
+	Mapping:  cpuM,
+}
+
 var aggTests = map[string]aggTest{
-	"precise":         {true, true, true, true, 5},
-	"fileline":        {false, true, true, true, 4},
-	"inline_function": {false, true, false, true, 3},
-	"function":        {false, true, false, false, 2},
+	"precise":         {true, true, true, true, true, 6},
+	"columns":         {false, true, true, true, true, 5},
+	"fileline":        {false, true, true, false, true, 4},
+	"inline_function": {false, true, false, false, true, 3},
+	"function":        {false, true, false, false, false, 2},
 }
 
 type aggTest struct {
-	precise, function, fileline, inlineFrame bool
-	rows                                     int
+	precise, function, fileline, column, inlineFrame bool
+	rows                                             int
 }
 
-const totalSamples = int64(11111)
+// totalSamples is the sum of sample.Value[0] for testProfile6.
+const totalSamples = int64(11112)
 
 func TestAggregation(t *testing.T) {
-	prof := testProfile1.Copy()
-	for _, resolution := range []string{"precise", "fileline", "inline_function", "function"} {
+	prof := testProfile6.Copy()
+	for _, resolution := range []string{"precise", "columns", "fileline", "inline_function", "function"} {
 		a := aggTests[resolution]
 		if !a.precise {
-			if err := prof.Aggregate(a.inlineFrame, a.function, a.fileline, a.fileline, false); err != nil {
+			if err := prof.Aggregate(a.inlineFrame, a.function, a.fileline, a.fileline, a.column, false); err != nil {
 				t.Error("aggregating to " + resolution + ":" + err.Error())
 			}
 		}
@@ -638,6 +713,9 @@ func checkAggregation(prof *Profile, a *aggTest) error {
 		}
 
 		for _, ln := range l.Line {
+			if !a.column && ln.Column != 0 {
+				return fmt.Errorf("found column %d on location %d, want:0", ln.Column, l.ID)
+			}
 			if !a.fileline && (ln.Function.Filename != "" || ln.Line != 0) {
 				return fmt.Errorf("found line %s:%d on location %d, want :0",
 					ln.Function.Filename, ln.Line, l.ID)
@@ -753,7 +831,7 @@ func TestMerge(t *testing.T) {
 	}
 
 	// Use aggregation to merge locations at function granularity.
-	if err := prof.Aggregate(false, true, false, false, false); err != nil {
+	if err := prof.Aggregate(false, true, false, false, false, false); err != nil {
 		t.Errorf("aggregating after merge: %v", err)
 	}
 
@@ -900,7 +978,7 @@ func TestEmptyMappingMerge(t *testing.T) {
 	}
 
 	// Use aggregation to merge locations at function granularity.
-	if err := prof.Aggregate(false, true, false, false, false); err != nil {
+	if err := prof.Aggregate(false, true, false, false, false, false); err != nil {
 		t.Errorf("aggregating after merge: %v", err)
 	}
 
@@ -997,7 +1075,7 @@ func locationHash(s *Sample) string {
 	var tb string
 	for _, l := range s.Location {
 		for _, ln := range l.Line {
-			tb = tb + fmt.Sprintf("%s:%d@%d ", ln.Function.Name, ln.Line, l.Address)
+			tb = tb + fmt.Sprintf("%s:%d:%d@%d ", ln.Function.Name, ln.Line, ln.Column, l.Address)
 		}
 	}
 	return tb
diff --git a/profile/prune_test.go b/profile/prune_test.go
index 75d7c6d4f..aaf76b99a 100644
--- a/profile/prune_test.go
+++ b/profile/prune_test.go
@@ -61,7 +61,7 @@ var locs1 = []*Location{
 	{
 		ID: 1,
 		Line: []Line{
-			{Function: funs[0], Line: 1},
+			{Function: funs[0], Line: 1, Column: 7},
 		},
 	},
 	{
@@ -75,7 +75,7 @@ var locs1 = []*Location{
 		ID: 3,
 		Line: []Line{
 			{Function: funs[3], Line: 2},
-			{Function: funs[1], Line: 1},
+			{Function: funs[1], Line: 1, Column: 7},
 		},
 	},
 	{
@@ -135,11 +135,11 @@ samples/count cpu/milliseconds
           1          1: 4 1
           1          1: 2 1
 Locations
-     1: 0x0 main main.c:1 s=0
-     2: 0x0 fun2 fun.c:1 s=0
-     3: 0x0 fun3 fun.c:2 s=0
-             fun1 fun.c:1 s=0
-     4: 0x0 fun5 fun.c:2 s=0
+     1: 0x0 main main.c:1:7 s=0
+     2: 0x0 fun2 fun.c:1:0 s=0
+     3: 0x0 fun3 fun.c:2:0 s=0
+             fun1 fun.c:1:7 s=0
+     4: 0x0 fun5 fun.c:2:0 s=0
 Mappings
 `
 
@@ -221,10 +221,10 @@ samples/count cpu/milliseconds
           1          1: 4 1
           1          1: 1
 Locations
-     1: 0x0 main main.c:1 s=0
-     2: 0x0 unsimplified_fun(int) fun.c:1 s=0
-     3: 0x0 Foo::(anonymous namespace)::Test::Bar fun.c:1 s=0
-     4: 0x0 Hello::(anonymous namespace)::World(const Foo::(anonymous namespace)::Test::Bar) fun.c:1 s=0
-     5: 0x0 Foo::operator()(::Bar) fun.c:1 s=0
+     1: 0x0 main main.c:1:0 s=0
+     2: 0x0 unsimplified_fun(int) fun.c:1:0 s=0
+     3: 0x0 Foo::(anonymous namespace)::Test::Bar fun.c:1:0 s=0
+     4: 0x0 Hello::(anonymous namespace)::World(const Foo::(anonymous namespace)::Test::Bar) fun.c:1:0 s=0
+     5: 0x0 Foo::operator()(::Bar) fun.c:1:0 s=0
 Mappings
 `
diff --git a/profile/testdata/java.contention.string b/profile/testdata/java.contention.string
index 985ffe1cc..34b811d09 100644
--- a/profile/testdata/java.contention.string
+++ b/profile/testdata/java.contention.string
@@ -8,36 +8,36 @@ contentions/count delay/microseconds
         200        200: 1 2 
         300        200: 30 31 32 
 Locations
-     1: 0x0 com.example.function03 source.java:3 s=0
-     2: 0x0 com.example.function04 source.java:4 s=0
-     3: 0x0 com.example.function0d source.java:0 s=0
-     4: 0x0 com.example.function0e source.java:0 s=0
-     5: 0x0 com.example.function0f source.java:0 s=0
-     6: 0x0 com.example.function10 source.java:10 s=0
-     7: 0x0 com.example.function11 source.java:11 s=0
-     8: 0x0 com.example.function12 source.java:12 s=0
-     9: 0x0 com.example.function13 source.java:13 s=0
-    10: 0x0 com.example.function14 source.java:14 s=0
-    11: 0x0 com.example.function17 source.java:17 s=0
-    12: 0x0 com.example.function18 source.java:18 s=0
-    13: 0x0 com.example.function19 source.java:19 s=0
-    14: 0x0 com.example.function1a source.java:1 s=0
-    15: 0x0 com.example.function1b source.java:1 s=0
-    16: 0x0 com.example.function1c source.java:1 s=0
-    17: 0x0 com.example.function29 source.java:29 s=0
-    18: 0x0 com.example.function2a source.java:2 s=0
-    19: 0x0 com.example.function2b source.java:2 s=0
-    20: 0x0 com.example.function2c source.java:2 s=0
-    21: 0x0 com.example.function2d source.java:2 s=0
-    22: 0x0 com.example.function2e source.java:2 s=0
-    23: 0x0 com.example.function2f source.java:2 s=0
-    24: 0x0 com.example.function30 source.java:30 s=0
-    25: 0x0 com.example.function31 source.java:31 s=0
-    26: 0x0 com.example.function32 source.java:32 s=0
-    27: 0x0 com.example.function33 source.java:33 s=0
-    28: 0x0 com.example.function34 source.java:34 s=0
-    29: 0x0 com.example.function35 source.java:35 s=0
-    30: 0x0 com.example.function36 source.java:36 s=0
-    31: 0x0 com.example.function37 source.java:37 s=0
-    32: 0x0 com.example.function38 source.java:38 s=0
+     1: 0x0 com.example.function03 source.java:3:0 s=0
+     2: 0x0 com.example.function04 source.java:4:0 s=0
+     3: 0x0 com.example.function0d source.java:0:0 s=0
+     4: 0x0 com.example.function0e source.java:0:0 s=0
+     5: 0x0 com.example.function0f source.java:0:0 s=0
+     6: 0x0 com.example.function10 source.java:10:0 s=0
+     7: 0x0 com.example.function11 source.java:11:0 s=0
+     8: 0x0 com.example.function12 source.java:12:0 s=0
+     9: 0x0 com.example.function13 source.java:13:0 s=0
+    10: 0x0 com.example.function14 source.java:14:0 s=0
+    11: 0x0 com.example.function17 source.java:17:0 s=0
+    12: 0x0 com.example.function18 source.java:18:0 s=0
+    13: 0x0 com.example.function19 source.java:19:0 s=0
+    14: 0x0 com.example.function1a source.java:1:0 s=0
+    15: 0x0 com.example.function1b source.java:1:0 s=0
+    16: 0x0 com.example.function1c source.java:1:0 s=0
+    17: 0x0 com.example.function29 source.java:29:0 s=0
+    18: 0x0 com.example.function2a source.java:2:0 s=0
+    19: 0x0 com.example.function2b source.java:2:0 s=0
+    20: 0x0 com.example.function2c source.java:2:0 s=0
+    21: 0x0 com.example.function2d source.java:2:0 s=0
+    22: 0x0 com.example.function2e source.java:2:0 s=0
+    23: 0x0 com.example.function2f source.java:2:0 s=0
+    24: 0x0 com.example.function30 source.java:30:0 s=0
+    25: 0x0 com.example.function31 source.java:31:0 s=0
+    26: 0x0 com.example.function32 source.java:32:0 s=0
+    27: 0x0 com.example.function33 source.java:33:0 s=0
+    28: 0x0 com.example.function34 source.java:34:0 s=0
+    29: 0x0 com.example.function35 source.java:35:0 s=0
+    30: 0x0 com.example.function36 source.java:36:0 s=0
+    31: 0x0 com.example.function37 source.java:37:0 s=0
+    32: 0x0 com.example.function38 source.java:38:0 s=0
 Mappings
diff --git a/profile/testdata/java.cpu.string b/profile/testdata/java.cpu.string
index f728cf26a..e15decbfe 100644
--- a/profile/testdata/java.cpu.string
+++ b/profile/testdata/java.cpu.string
@@ -11,68 +11,68 @@ samples/count cpu/nanoseconds
           1   10000000: 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 29 30 31 32 
           1   10000000: 54 55 56 57 58 59 60 61 62 11 63 64 16 17 18 
 Locations
-     1: 0x0 GC :0 s=0
-     2: 0x0 Compile :0 s=0
-     3: 0x0 VM :0 s=0
-     4: 0x0 com.example.function06 source.java:6 s=0
-     5: 0x0 com.example.function07 source.java:7 s=0
-     6: 0x0 com.example.function08 source.java:8 s=0
-     7: 0x0 com.example.function09 source.java:9 s=0
-     8: 0x0 com.example.function0a source.java:0 s=0
-     9: 0x0 com.example.function0b source.java:0 s=0
-    10: 0x0 com.example.function0c source.java:0 s=0
-    11: 0x0 com.example.function0d source.java:0 s=0
-    12: 0x0 com.example.function0e source.java:0 s=0
-    13: 0x0 com.example.function0f source.java:0 s=0
-    14: 0x0 com.example.function10 source.java:10 s=0
-    15: 0x0 com.example.function11 source.java:11 s=0
-    16: 0x0 com.example.function12 source.java:12 s=0
-    17: 0x0 com.example.function13 source.java:13 s=0
-    18: 0x0 com.example.function14 source.java:14 s=0
-    19: 0x0 com.example.function1d source.java:1 s=0
-    20: 0x0 com.example.function1e source.java:1 s=0
-    21: 0x0 com.example.function1f source.java:1 s=0
-    22: 0x0 com.example.function20 source.java:20 s=0
-    23: 0x0 com.example.function21 source.java:21 s=0
-    24: 0x0 com.example.function22 source.java:22 s=0
-    25: 0x0 com.example.function23 source.java:23 s=0
-    26: 0x0 com.example.function24 source.java:24 s=0
-    27: 0x0 com.example.function25 source.java:25 s=0
-    28: 0x0 com.example.function26 source.java:26 s=0
-    29: 0x0 com.example.function27 source.java:27 s=0
-    30: 0x0 com.example.function28 source.java:28 s=0
-    31: 0x0 com.example.function29 source.java:29 s=0
-    32: 0x0 com.example.function2a source.java:2 s=0
-    33: 0x0 com.example.function2b source.java:2 s=0
-    34: 0x0 com.example.function2c source.java:2 s=0
-    35: 0x0 com.example.function2d source.java:2 s=0
-    36: 0x0 com.example.function2e source.java:2 s=0
-    37: 0x0 com.example.function2f source.java:2 s=0
-    38: 0x0 com.example.function30 source.java:30 s=0
-    39: 0x0 com.example.function31 source.java:31 s=0
-    40: 0x0 com.example.function32 source.java:32 s=0
-    41: 0x0 com.example.function33 source.java:33 s=0
-    42: 0x0 com.example.function34 source.java:34 s=0
-    43: 0x0 com.example.function35 source.java:35 s=0
-    44: 0x0 com.example.function36 source.java:36 s=0
-    45: 0x0 com.example.function37 source.java:37 s=0
-    46: 0x0 com.example.function38 source.java:38 s=0
-    47: 0x0 com.example.function39 source.java:39 s=0
-    48: 0x0 com.example.function3a source.java:3 s=0
-    49: 0x0 com.example.function3b source.java:3 s=0
-    50: 0x0 com.example.function3c source.java:3 s=0
-    51: 0x0 com.example.function3d source.java:3 s=0
-    52: 0x0 com.example.function3e source.java:3 s=0
-    53: 0x0 com.example.function3f source.java:3 s=0
-    54: 0x0 com.example.function40 source.java:40 s=0
-    55: 0x0 com.example.function41 source.java:41 s=0
-    56: 0x0 com.example.function42 source.java:42 s=0
-    57: 0x0 com.example.function43 source.java:43 s=0
-    58: 0x0 com.example.function44 source.java:44 s=0
-    59: 0x0 com.example.function45 source.java:45 s=0
-    60: 0x0 com.example.function46 source.java:46 s=0
-    61: 0x0 com.example.function47 source.java:47 s=0
-    62: 0x0 com.example.function48 source.java:48 s=0
-    63: 0x0 com.example.function49 source.java:49 s=0
-    64: 0x0 com.example.function4a source.java:4 s=0
+     1: 0x0 GC :0:0 s=0
+     2: 0x0 Compile :0:0 s=0
+     3: 0x0 VM :0:0 s=0
+     4: 0x0 com.example.function06 source.java:6:0 s=0
+     5: 0x0 com.example.function07 source.java:7:0 s=0
+     6: 0x0 com.example.function08 source.java:8:0 s=0
+     7: 0x0 com.example.function09 source.java:9:0 s=0
+     8: 0x0 com.example.function0a source.java:0:0 s=0
+     9: 0x0 com.example.function0b source.java:0:0 s=0
+    10: 0x0 com.example.function0c source.java:0:0 s=0
+    11: 0x0 com.example.function0d source.java:0:0 s=0
+    12: 0x0 com.example.function0e source.java:0:0 s=0
+    13: 0x0 com.example.function0f source.java:0:0 s=0
+    14: 0x0 com.example.function10 source.java:10:0 s=0
+    15: 0x0 com.example.function11 source.java:11:0 s=0
+    16: 0x0 com.example.function12 source.java:12:0 s=0
+    17: 0x0 com.example.function13 source.java:13:0 s=0
+    18: 0x0 com.example.function14 source.java:14:0 s=0
+    19: 0x0 com.example.function1d source.java:1:0 s=0
+    20: 0x0 com.example.function1e source.java:1:0 s=0
+    21: 0x0 com.example.function1f source.java:1:0 s=0
+    22: 0x0 com.example.function20 source.java:20:0 s=0
+    23: 0x0 com.example.function21 source.java:21:0 s=0
+    24: 0x0 com.example.function22 source.java:22:0 s=0
+    25: 0x0 com.example.function23 source.java:23:0 s=0
+    26: 0x0 com.example.function24 source.java:24:0 s=0
+    27: 0x0 com.example.function25 source.java:25:0 s=0
+    28: 0x0 com.example.function26 source.java:26:0 s=0
+    29: 0x0 com.example.function27 source.java:27:0 s=0
+    30: 0x0 com.example.function28 source.java:28:0 s=0
+    31: 0x0 com.example.function29 source.java:29:0 s=0
+    32: 0x0 com.example.function2a source.java:2:0 s=0
+    33: 0x0 com.example.function2b source.java:2:0 s=0
+    34: 0x0 com.example.function2c source.java:2:0 s=0
+    35: 0x0 com.example.function2d source.java:2:0 s=0
+    36: 0x0 com.example.function2e source.java:2:0 s=0
+    37: 0x0 com.example.function2f source.java:2:0 s=0
+    38: 0x0 com.example.function30 source.java:30:0 s=0
+    39: 0x0 com.example.function31 source.java:31:0 s=0
+    40: 0x0 com.example.function32 source.java:32:0 s=0
+    41: 0x0 com.example.function33 source.java:33:0 s=0
+    42: 0x0 com.example.function34 source.java:34:0 s=0
+    43: 0x0 com.example.function35 source.java:35:0 s=0
+    44: 0x0 com.example.function36 source.java:36:0 s=0
+    45: 0x0 com.example.function37 source.java:37:0 s=0
+    46: 0x0 com.example.function38 source.java:38:0 s=0
+    47: 0x0 com.example.function39 source.java:39:0 s=0
+    48: 0x0 com.example.function3a source.java:3:0 s=0
+    49: 0x0 com.example.function3b source.java:3:0 s=0
+    50: 0x0 com.example.function3c source.java:3:0 s=0
+    51: 0x0 com.example.function3d source.java:3:0 s=0
+    52: 0x0 com.example.function3e source.java:3:0 s=0
+    53: 0x0 com.example.function3f source.java:3:0 s=0
+    54: 0x0 com.example.function40 source.java:40:0 s=0
+    55: 0x0 com.example.function41 source.java:41:0 s=0
+    56: 0x0 com.example.function42 source.java:42:0 s=0
+    57: 0x0 com.example.function43 source.java:43:0 s=0
+    58: 0x0 com.example.function44 source.java:44:0 s=0
+    59: 0x0 com.example.function45 source.java:45:0 s=0
+    60: 0x0 com.example.function46 source.java:46:0 s=0
+    61: 0x0 com.example.function47 source.java:47:0 s=0
+    62: 0x0 com.example.function48 source.java:48:0 s=0
+    63: 0x0 com.example.function49 source.java:49:0 s=0
+    64: 0x0 com.example.function4a source.java:4:0 s=0
 Mappings
diff --git a/profile/testdata/java.heap.string b/profile/testdata/java.heap.string
index 261bee13a..5e1b549d3 100644
--- a/profile/testdata/java.heap.string
+++ b/profile/testdata/java.heap.string
@@ -17,123 +17,123 @@ inuse_objects/count inuse_space/bytes
       54615    2621560: 119 
                 bytes:[48]
 Locations
-     1: 0x0 com.example.function003 Source003.java:103 s=0
-     2: 0x0 com.example.function004 Source004.java:104 s=0
-     3: 0x0 com.example.function005 Source005.java:105 s=0
-     4: 0x0 com.example.function006 Source006.java:106 s=0
-     5: 0x0 com.example.function007 Source007.java:107 s=0
-     6: 0x0 com.example.function008 Source008.java:108 s=0
-     7: 0x0 com.example.function009 Source009.java:109 s=0
-     8: 0x0 com.example.function00a Source00a.java:10 s=0
-     9: 0x0 com.example.function00b Source00b.java:10 s=0
-    10: 0x0 com.example.function00c Source00c.java:10 s=0
-    11: 0x0 com.example.function00d Source00d.java:10 s=0
-    12: 0x0 com.example.function00e Source00e.java:10 s=0
-    13: 0x0 com.example.function00f Source00f.java:10 s=0
-    14: 0x0 com.example.function010 Source010.java:110 s=0
-    15: 0x0 com.example.function011 Source011.java:111 s=0
-    16: 0x0 com.example.function018 Source018.java:118 s=0
-    17: 0x0 com.example.function019 Source019.java:119 s=0
-    18: 0x0 com.example.function01a Source01a.java:11 s=0
-    19: 0x0 com.example.function01b Source01b.java:11 s=0
-    20: 0x0 com.example.function01c Source01c.java:11 s=0
-    21: 0x0 com.example.function01d Source01d.java:11 s=0
-    22: 0x0 com.example.function01e Source01e.java:11 s=0
-    23: 0x0 com.example.function01f Source01f.java:11 s=0
-    24: 0x0 com.example.function020 Source020.java:120 s=0
-    25: 0x0 com.example.function021 Source021.java:121 s=0
-    26: 0x0 com.example.function022 Source022.java:122 s=0
-    27: 0x0 com.example.function023 Source023.java:123 s=0
-    28: 0x0 com.example.function024 Source024.java:124 s=0
-    29: 0x0 com.example.function025 Source025.java:125 s=0
-    30: 0x0 com.example.function026 Source026.java:126 s=0
-    31: 0x0 com.example.function027 Source027.java:127 s=0
-    32: 0x0 com.example.function028 Source028.java:128 s=0
-    33: 0x0 com.example.function029 Source029.java:129 s=0
-    34: 0x0 com.example.function02a Source02a.java:12 s=0
-    35: 0x0 com.example.function02b Source02b.java:12 s=0
-    36: 0x0 com.example.function02c Source02c.java:12 s=0
-    37: 0x0 com.example.function02d Source02d.java:12 s=0
-    38: 0x0 com.example.function02e Source02e.java:12 s=0
-    39: 0x0 com.example.function035 Source035.java:135 s=0
-    40: 0x0 com.example.function036 Source036.java:136 s=0
-    41: 0x0 com.example.function037 Source037.java:137 s=0
-    42: 0x0 com.example.function038 Source038.java:138 s=0
-    43: 0x0 com.example.function039 Source039.java:139 s=0
-    44: 0x0 com.example.function03a Source03a.java:13 s=0
-    45: 0x0 com.example.function03b Source03b.java:13 s=0
-    46: 0x0 com.example.function03d Source03d.java:13 s=0
-    47: 0x0 com.example.function03e Source03e.java:13 s=0
-    48: 0x0 com.example.function03f Source03f.java:13 s=0
-    49: 0x0 com.example.function040 Source040.java:140 s=0
-    50: 0x0 com.example.function041 Source041.java:141 s=0
-    51: 0x0 com.example.function042 Source042.java:142 s=0
-    52: 0x0 com.example.function049 Source049.java:149 s=0
-    53: 0x0 com.example.function04a Source04a.java:14 s=0
-    54: 0x0 com.example.function04b Source04b.java:14 s=0
-    55: 0x0 com.example.function04c Source04c.java:14 s=0
-    56: 0x0 com.example.function04d Source04d.java:14 s=0
-    57: 0x0 com.example.function04e Source04e.java:14 s=0
-    58: 0x0 com.example.function04f Source04f.java:14 s=0
-    59: 0x0 com.example.function050 Source050.java:150 s=0
-    60: 0x0 com.example.function051 Source051.java:151 s=0
-    61: 0x0 com.example.function052 Source052.java:152 s=0
-    62: 0x0 com.example.function053 Source053.java:153 s=0
-    63: 0x0 com.example.function054 Source054.java:154 s=0
-    64: 0x0 com.example.function055 Source055.java:155 s=0
-    65: 0x0 com.example.function056 Source056.java:156 s=0
-    66: 0x0 com.example.function057 Source057.java:157 s=0
-    67: 0x0 com.example.function05e Source05e.java:15 s=0
-    68: 0x0 com.example.function05f Source05f.java:15 s=0
-    69: 0x0 com.example.function060 Source060.java:160 s=0
-    70: 0x0 com.example.function061 Source061.java:161 s=0
-    71: 0x0 com.example.function062 Source062.java:162 s=0
-    72: 0x0 com.example.function063 Source063.java:163 s=0
-    73: 0x0 com.example.function064 Source064.java:164 s=0
-    74: 0x0 com.example.function065 Source065.java:165 s=0
-    75: 0x0 com.example.function066 Source066.java:166 s=0
-    76: 0x0 com.example.function067 Source067.java:167 s=0
-    77: 0x0 com.example.function068 Source068.java:168 s=0
-    78: 0x0 com.example.function069 Source069.java:169 s=0
-    79: 0x0 com.example.function06a Source06a.java:16 s=0
-    80: 0x0 com.example.function06b Source06b.java:16 s=0
-    81: 0x0 com.example.function06c Source06c.java:16 s=0
-    82: 0x0 com.example.function06d Source06d.java:16 s=0
-    83: 0x0 com.example.function06e Source06e.java:16 s=0
-    84: 0x0 com.example.function06f Source06f.java:16 s=0
-    85: 0x0 com.example.function070 Source070.java:170 s=0
-    86: 0x0 com.example.function071 Source071.java:171 s=0
-    87: 0x0 com.example.function072 Source072.java:172 s=0
-    88: 0x0 com.example.function073 Source073.java:173 s=0
-    89: 0x0 com.example.function074 Source074.java:174 s=0
-    90: 0x0 com.example.function075 Source075.java:175 s=0
-    91: 0x0 com.example.function076 Source076.java:176 s=0
-    92: 0x0 com.example.function077 Source077.java:177 s=0
-    93: 0x0 com.example.function078 Source078.java:178 s=0
-    94: 0x0 com.example.function079 Source079.java:179 s=0
-    95: 0x0 com.example.function07a Source07a.java:17 s=0
-    96: 0x0 com.example.function07b Source07b.java:17 s=0
-    97: 0x0 com.example.function081 Source081.java:181 s=0
-    98: 0x0 com.example.function082 Source082.java:182 s=0
-    99: 0x0 com.example.function083 Source083.java:183 s=0
-   100: 0x0 com.example.function084 Source084.java:184 s=0
-   101: 0x0 com.example.function085 Source085.java:185 s=0
-   102: 0x0 com.example.function086 Source086.java:186 s=0
-   103: 0x0 com.example.function087 Source087.java:187 s=0
-   104: 0x0 com.example.function088 Source088.java:188 s=0
-   105: 0x0 com.example.function089 Source089.java:189 s=0
-   106: 0x0 com.example.function08a Source08a.java:18 s=0
-   107: 0x0 com.example.function08b Source08b.java:18 s=0
-   108: 0x0 com.example.function08c Source08c.java:18 s=0
-   109: 0x0 com.example.function08d Source08d.java:18 s=0
-   110: 0x0 com.example.function08e Source08e.java:18 s=0
-   111: 0x0 com.example.function08f Source08f.java:18 s=0
-   112: 0x0 com.example.function090 Source090.java:190 s=0
-   113: 0x0 com.example.function091 Source091.java:191 s=0
-   114: 0x0 com.example.function092 Source092.java:192 s=0
-   115: 0x0 com.example.function093 Source093.java:193 s=0
-   116: 0x0 com.example.function094 Source094.java:194 s=0
-   117: 0x0 com.example.function095 Source095.java:195 s=0
-   118: 0x0 com.example.function096 Source096.java:196 s=0
-   119: 0x0 com.example.function097 Source097.java:197 s=0
+     1: 0x0 com.example.function003 Source003.java:103:0 s=0
+     2: 0x0 com.example.function004 Source004.java:104:0 s=0
+     3: 0x0 com.example.function005 Source005.java:105:0 s=0
+     4: 0x0 com.example.function006 Source006.java:106:0 s=0
+     5: 0x0 com.example.function007 Source007.java:107:0 s=0
+     6: 0x0 com.example.function008 Source008.java:108:0 s=0
+     7: 0x0 com.example.function009 Source009.java:109:0 s=0
+     8: 0x0 com.example.function00a Source00a.java:10:0 s=0
+     9: 0x0 com.example.function00b Source00b.java:10:0 s=0
+    10: 0x0 com.example.function00c Source00c.java:10:0 s=0
+    11: 0x0 com.example.function00d Source00d.java:10:0 s=0
+    12: 0x0 com.example.function00e Source00e.java:10:0 s=0
+    13: 0x0 com.example.function00f Source00f.java:10:0 s=0
+    14: 0x0 com.example.function010 Source010.java:110:0 s=0
+    15: 0x0 com.example.function011 Source011.java:111:0 s=0
+    16: 0x0 com.example.function018 Source018.java:118:0 s=0
+    17: 0x0 com.example.function019 Source019.java:119:0 s=0
+    18: 0x0 com.example.function01a Source01a.java:11:0 s=0
+    19: 0x0 com.example.function01b Source01b.java:11:0 s=0
+    20: 0x0 com.example.function01c Source01c.java:11:0 s=0
+    21: 0x0 com.example.function01d Source01d.java:11:0 s=0
+    22: 0x0 com.example.function01e Source01e.java:11:0 s=0
+    23: 0x0 com.example.function01f Source01f.java:11:0 s=0
+    24: 0x0 com.example.function020 Source020.java:120:0 s=0
+    25: 0x0 com.example.function021 Source021.java:121:0 s=0
+    26: 0x0 com.example.function022 Source022.java:122:0 s=0
+    27: 0x0 com.example.function023 Source023.java:123:0 s=0
+    28: 0x0 com.example.function024 Source024.java:124:0 s=0
+    29: 0x0 com.example.function025 Source025.java:125:0 s=0
+    30: 0x0 com.example.function026 Source026.java:126:0 s=0
+    31: 0x0 com.example.function027 Source027.java:127:0 s=0
+    32: 0x0 com.example.function028 Source028.java:128:0 s=0
+    33: 0x0 com.example.function029 Source029.java:129:0 s=0
+    34: 0x0 com.example.function02a Source02a.java:12:0 s=0
+    35: 0x0 com.example.function02b Source02b.java:12:0 s=0
+    36: 0x0 com.example.function02c Source02c.java:12:0 s=0
+    37: 0x0 com.example.function02d Source02d.java:12:0 s=0
+    38: 0x0 com.example.function02e Source02e.java:12:0 s=0
+    39: 0x0 com.example.function035 Source035.java:135:0 s=0
+    40: 0x0 com.example.function036 Source036.java:136:0 s=0
+    41: 0x0 com.example.function037 Source037.java:137:0 s=0
+    42: 0x0 com.example.function038 Source038.java:138:0 s=0
+    43: 0x0 com.example.function039 Source039.java:139:0 s=0
+    44: 0x0 com.example.function03a Source03a.java:13:0 s=0
+    45: 0x0 com.example.function03b Source03b.java:13:0 s=0
+    46: 0x0 com.example.function03d Source03d.java:13:0 s=0
+    47: 0x0 com.example.function03e Source03e.java:13:0 s=0
+    48: 0x0 com.example.function03f Source03f.java:13:0 s=0
+    49: 0x0 com.example.function040 Source040.java:140:0 s=0
+    50: 0x0 com.example.function041 Source041.java:141:0 s=0
+    51: 0x0 com.example.function042 Source042.java:142:0 s=0
+    52: 0x0 com.example.function049 Source049.java:149:0 s=0
+    53: 0x0 com.example.function04a Source04a.java:14:0 s=0
+    54: 0x0 com.example.function04b Source04b.java:14:0 s=0
+    55: 0x0 com.example.function04c Source04c.java:14:0 s=0
+    56: 0x0 com.example.function04d Source04d.java:14:0 s=0
+    57: 0x0 com.example.function04e Source04e.java:14:0 s=0
+    58: 0x0 com.example.function04f Source04f.java:14:0 s=0
+    59: 0x0 com.example.function050 Source050.java:150:0 s=0
+    60: 0x0 com.example.function051 Source051.java:151:0 s=0
+    61: 0x0 com.example.function052 Source052.java:152:0 s=0
+    62: 0x0 com.example.function053 Source053.java:153:0 s=0
+    63: 0x0 com.example.function054 Source054.java:154:0 s=0
+    64: 0x0 com.example.function055 Source055.java:155:0 s=0
+    65: 0x0 com.example.function056 Source056.java:156:0 s=0
+    66: 0x0 com.example.function057 Source057.java:157:0 s=0
+    67: 0x0 com.example.function05e Source05e.java:15:0 s=0
+    68: 0x0 com.example.function05f Source05f.java:15:0 s=0
+    69: 0x0 com.example.function060 Source060.java:160:0 s=0
+    70: 0x0 com.example.function061 Source061.java:161:0 s=0
+    71: 0x0 com.example.function062 Source062.java:162:0 s=0
+    72: 0x0 com.example.function063 Source063.java:163:0 s=0
+    73: 0x0 com.example.function064 Source064.java:164:0 s=0
+    74: 0x0 com.example.function065 Source065.java:165:0 s=0
+    75: 0x0 com.example.function066 Source066.java:166:0 s=0
+    76: 0x0 com.example.function067 Source067.java:167:0 s=0
+    77: 0x0 com.example.function068 Source068.java:168:0 s=0
+    78: 0x0 com.example.function069 Source069.java:169:0 s=0
+    79: 0x0 com.example.function06a Source06a.java:16:0 s=0
+    80: 0x0 com.example.function06b Source06b.java:16:0 s=0
+    81: 0x0 com.example.function06c Source06c.java:16:0 s=0
+    82: 0x0 com.example.function06d Source06d.java:16:0 s=0
+    83: 0x0 com.example.function06e Source06e.java:16:0 s=0
+    84: 0x0 com.example.function06f Source06f.java:16:0 s=0
+    85: 0x0 com.example.function070 Source070.java:170:0 s=0
+    86: 0x0 com.example.function071 Source071.java:171:0 s=0
+    87: 0x0 com.example.function072 Source072.java:172:0 s=0
+    88: 0x0 com.example.function073 Source073.java:173:0 s=0
+    89: 0x0 com.example.function074 Source074.java:174:0 s=0
+    90: 0x0 com.example.function075 Source075.java:175:0 s=0
+    91: 0x0 com.example.function076 Source076.java:176:0 s=0
+    92: 0x0 com.example.function077 Source077.java:177:0 s=0
+    93: 0x0 com.example.function078 Source078.java:178:0 s=0
+    94: 0x0 com.example.function079 Source079.java:179:0 s=0
+    95: 0x0 com.example.function07a Source07a.java:17:0 s=0
+    96: 0x0 com.example.function07b Source07b.java:17:0 s=0
+    97: 0x0 com.example.function081 Source081.java:181:0 s=0
+    98: 0x0 com.example.function082 Source082.java:182:0 s=0
+    99: 0x0 com.example.function083 Source083.java:183:0 s=0
+   100: 0x0 com.example.function084 Source084.java:184:0 s=0
+   101: 0x0 com.example.function085 Source085.java:185:0 s=0
+   102: 0x0 com.example.function086 Source086.java:186:0 s=0
+   103: 0x0 com.example.function087 Source087.java:187:0 s=0
+   104: 0x0 com.example.function088 Source088.java:188:0 s=0
+   105: 0x0 com.example.function089 Source089.java:189:0 s=0
+   106: 0x0 com.example.function08a Source08a.java:18:0 s=0
+   107: 0x0 com.example.function08b Source08b.java:18:0 s=0
+   108: 0x0 com.example.function08c Source08c.java:18:0 s=0
+   109: 0x0 com.example.function08d Source08d.java:18:0 s=0
+   110: 0x0 com.example.function08e Source08e.java:18:0 s=0
+   111: 0x0 com.example.function08f Source08f.java:18:0 s=0
+   112: 0x0 com.example.function090 Source090.java:190:0 s=0
+   113: 0x0 com.example.function091 Source091.java:191:0 s=0
+   114: 0x0 com.example.function092 Source092.java:192:0 s=0
+   115: 0x0 com.example.function093 Source093.java:193:0 s=0
+   116: 0x0 com.example.function094 Source094.java:194:0 s=0
+   117: 0x0 com.example.function095 Source095.java:195:0 s=0
+   118: 0x0 com.example.function096 Source096.java:196:0 s=0
+   119: 0x0 com.example.function097 Source097.java:197:0 s=0
 Mappings
diff --git a/proto/profile.proto b/proto/profile.proto
index c41ec50e8..ff987a617 100644
--- a/proto/profile.proto
+++ b/proto/profile.proto
@@ -208,6 +208,8 @@ message Line {
   uint64 function_id = 1;
   // Line number in source code.
   int64 line = 2;
+  // Column number in source code.
+  int64 column = 3;
 }
 
 message Function {