Cleanup FUZZTEST_STACK_LIMIT env var in favor of --stack_limit_kb flag.

PiperOrigin-RevId: 766227743

Author: saladq

e2e_tests/functional_test.cc

@@ -1102,32 +1102,6 @@ TEST_F(FuzzingModeCommandLineInterfaceTest, ConfiguresStackLimitByFlag) {
   ExpectTargetAbort(status, std_err);
 }
 
-TEST_F(FuzzingModeCommandLineInterfaceTest,
-       ConfiguresStackLimitByEnvVarWithWarning) {
-  auto [status, std_out, std_err] =
-      RunWith({{"fuzz", "MySuite.DataDependentStackOverflow"}},
-              {{"FUZZTEST_STACK_LIMIT", "512000"}});
-  EXPECT_THAT(std_err, HasSubstr("argument 0: "));
-  EXPECT_THAT(std_err,
-              HasSubstr(absl::StrCat(
-                  "Stack limit is set by FUZZTEST_STACK_LIMIT env var - this "
-                  "is going to be deprecated soon. Consider switching to ",
-                  CreateFuzzTestFlag("stack_limit_kb", ""), " flag.")));
-  ExpectStackLimitExceededMessage(std_err, 512000);
-  ExpectTargetAbort(status, std_err);
-}
-
-TEST_F(FuzzingModeCommandLineInterfaceTest,
-       ConfiguresStackLimitByEnvVarAndOverridesFlag) {
-  auto [status, std_out, std_err] =
-      RunWith({{"fuzz", "MySuite.DataDependentStackOverflow"},
-               {"stack_limit_kb", "1000"}},
-              {{"FUZZTEST_STACK_LIMIT", "512000"}});
-  EXPECT_THAT(std_err, HasSubstr("argument 0: "));
-  ExpectStackLimitExceededMessage(std_err, 512000);
-  ExpectTargetAbort(status, std_err);
-}
-
 TEST_F(FuzzingModeCommandLineInterfaceTest,
        DoesNotPrintWarningForDisabledLimitFlagsByDefault) {
   auto [status, std_out, std_err] = RunWith(

fuzztest/internal/centipede_adaptor.cc

@@ -559,9 +559,7 @@ class CentipedeAdaptorRunnerCallbacks
 namespace {
 
 void PopulateTestLimitsToCentipedeRunner(const Configuration& configuration) {
-  if (const size_t stack_limit =
-          GetStackLimitFromEnvOrConfiguration(configuration);
-      stack_limit > 0) {
+  if (const size_t stack_limit = configuration.stack_limit; stack_limit > 0) {
     absl::FPrintF(GetStderr(), "[.] Stack limit set to: %zu\n", stack_limit);
     CentipedeSetStackLimit(/*stack_limit_kb=*/stack_limit >> 10);
   }

fuzztest/internal/runtime.cc

@@ -1010,30 +1010,12 @@ void FuzzTestFuzzerImpl::PopulateFromSeeds(
                });
 }
 
-size_t GetStackLimitFromEnvOrConfiguration(const Configuration& configuration) {
-  size_t env_stack_limit;
-  if (const char* env = getenv("FUZZTEST_STACK_LIMIT");
-      (env != nullptr && absl::SimpleAtoi(env, &env_stack_limit))) {
-    absl::FPrintF(
-        GetStderr(),
-        "[!] Stack limit is set by FUZZTEST_STACK_LIMIT env var - this is "
-        "going to be deprecated soon. Consider switching to "
-        "--" FUZZTEST_FLAG_PREFIX "stack_limit_kb flag.\n");
-    return env_stack_limit;
-  }
-  return configuration.stack_limit;
-}
-
 void PopulateLimits(const Configuration& configuration,
                     ExecutionCoverage* execution_coverage) {
   // centipede_adaptor would populate the limits to Centipede.
 #ifndef FUZZTEST_USE_CENTIPEDE
-  // TODO(b/273276918): For now, let existing FUZZTEST_STACK_LIMIT overwrite the
-  // stack limit. So that the existing targets that set the env var could still
-  // work.
   if (execution_coverage)
-    execution_coverage->SetStackLimit(
-        GetStackLimitFromEnvOrConfiguration(configuration));
+    execution_coverage->SetStackLimit(configuration.stack_limit);
 #endif
 }
 

fuzztest/internal/runtime.h

@@ -431,8 +431,6 @@ class FuzzTestFuzzerImpl : public FuzzTestFuzzer {
   friend class CentipedeAdaptorEngineCallbacks;
 };
 
-size_t GetStackLimitFromEnvOrConfiguration(const Configuration& configuration);
-
 // A reproduction command template will include these placeholders. These
 // placeholders then will be replaced by the proper test filter when creating
 // the final reproduction command from the template.