host-cpu-c-abi: Avoid use of 'grep -E' on OpenIndiana.

* m4/asm-underscore.m4 (gl_ASM_SYMBOL_PREFIX): Require AC_PROG_EGREP,
and use $EGREP instead of 'grep -E'.
* m4/host-cpu-c-abi.m4 (gl_HOST_CPU_C_ABI): Use 'grep' instead of
'grep -E'.

ChangeLog

@@ -1,3 +1,11 @@
+2018-02-03  Bruno Haible  <bruno@clisp.org>
+
+	host-cpu-c-abi: Avoid use of 'grep -E' on OpenIndiana.
+	* m4/asm-underscore.m4 (gl_ASM_SYMBOL_PREFIX): Require AC_PROG_EGREP,
+	and use $EGREP instead of 'grep -E'.
+	* m4/host-cpu-c-abi.m4 (gl_HOST_CPU_C_ABI): Use 'grep' instead of
+	'grep -E'.
+
 2018-02-02  Paul Eggert  <eggert@cs.ucla.edu>
 
 	malloca: Add a compile-time verification.

m4/asm-underscore.m4

@@ -1,4 +1,4 @@
-# asm-underscore.m4 serial 3
+# asm-underscore.m4 serial 4
 dnl Copyright (C) 2010-2018 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -14,6 +14,7 @@ dnl From Bruno Haible. Based on as-underscore.m4 in GNU clisp.
 
 AC_DEFUN([gl_ASM_SYMBOL_PREFIX],
 [
+  AC_REQUIRE([AC_PROG_EGREP])
   dnl We don't use GCC's __USER_LABEL_PREFIX__ here, because
   dnl 1. It works only for GCC.
   dnl 2. It is incorrectly defined on some platforms, in some GCC versions.
@@ -29,7 +30,7 @@ int foo(void) { return 0; }
 EOF
      # Look for the assembly language name in the .s file.
      AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $gl_c_asm_opt conftest.c) >/dev/null 2>&1
-     if LC_ALL=C grep -E '(^|[[^a-zA-Z0-9_]])_foo([[^a-zA-Z0-9_]]|$)' conftest.$gl_asmext >/dev/null; then
+     if LC_ALL=C $EGREP '(^|[[^a-zA-Z0-9_]])_foo([[^a-zA-Z0-9_]]|$)' conftest.$gl_asmext >/dev/null; then
        gl_cv_prog_as_underscore=yes
      else
        gl_cv_prog_as_underscore=no

m4/host-cpu-c-abi.m4

@@ -1,4 +1,4 @@
-# host-cpu-c-abi.m4 serial 8
+# host-cpu-c-abi.m4 serial 9
 dnl Copyright (C) 2002-2018 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -135,7 +135,7 @@ changequote([,])dnl
             echo 'double ddd; void func (double dd) { ddd = dd; }' > conftest.c
             # Look for a reference to the register d0 in the .s file.
             AC_TRY_COMMAND(${CC-cc} $CFLAGS $CPPFLAGS $gl_c_asm_opt conftest.c) >/dev/null 2>&1
-            if LC_ALL=C grep -E 'd0,' conftest.$gl_asmext >/dev/null; then
+            if LC_ALL=C grep 'd0,' conftest.$gl_asmext >/dev/null; then
               gl_cv_host_cpu_c_abi=armhf
             else
               gl_cv_host_cpu_c_abi=arm