[gcc(refs/users/xry111/heads/no-egrep-v2)] contrib: use grep -E instead of egrep

[gcc(refs/users/xry111/heads/no-egrep-v2)] contrib: use grep -E instead of egrep

[Xi Ruoyao]

https://gcc.gnu.org/g:ff60381b198e71257581f94ee98ccbe872ebc8dd

commit ff60381b198e71257581f94ee98ccbe872ebc8dd
Author: Xi Ruoyao <xry111@xry111.site>
Date:   Fri Jun 24 14:39:35 2022 +0800

    contrib: use grep -E instead of egrep
    
    egrep has been deprecated in favor of grep -E for a long time, and the
    next grep release (3.8 or 4.0) will print a warning of egrep is used.
    Stop using egrep so we won't see the warning.
    
    Some non-POSIX grep implementations does not support -E option, so for
    test_summary and warn_summary we prefer grep -E, but fallback to egrep
    if grep -E does not work.  For check_GNU_style.sh, I think it is only
    used by developers so hard coding grep -E is OK.
    
    contrib/ChangeLog:
    
            * check_GNU_style.sh: Use grep -E instead of egrep.
            * test_summary: Use grep -E instead of egrep if it works.
            * warn_summary: Likewise.

Diff:
---
 contrib/check_GNU_style.sh | 10 +++++-----
 contrib/test_summary       | 13 ++++++++++++-
 contrib/warn_summary       | 13 ++++++++++++-
 3 files changed, 29 insertions(+), 7 deletions(-)

diff --git a/contrib/check_GNU_style.sh b/contrib/check_GNU_style.sh
index fb7494661ee..535be65f063 100755
--- a/contrib/check_GNU_style.sh
+++ b/contrib/check_GNU_style.sh
@@ -113,7 +113,7 @@ g (){
 
     local found=false
     cat $inp \
-	| egrep $color -- "$arg" \
+	| grep -E $color -- "$arg" \
 	> "$tmp" && found=true
 
     if $found; then
@@ -130,8 +130,8 @@ ag (){
 
     local found=false
     cat $inp \
-	| egrep $color -- "$arg1" \
-	| egrep $color -- "$arg2" \
+	| grep -E $color -- "$arg1" \
+	| grep -E $color -- "$arg2" \
 	> "$tmp" && found=true
 
     if $found; then
@@ -148,8 +148,8 @@ vg (){
 
     local found=false
     cat $inp \
-	| egrep -v -- "$varg" \
-	| egrep $color -- "$arg" \
+	| grep -E -v -- "$varg" \
+	| grep -E $color -- "$arg" \
 	> "$tmp" && found=true
 
     if $found; then
diff --git a/contrib/test_summary b/contrib/test_summary
index 5760b053ec2..f17bf54f8ec 100755
--- a/contrib/test_summary
+++ b/contrib/test_summary
@@ -54,6 +54,17 @@ if test -z "$AWK" ; then
   done
 fi
 
+# Prefer "grep -E" which should work with POSIX-conform grep, but fallback
+# to "egrep" (which is deprecated for a long time) if grep does not support
+# -E.
+if test -z "$EGREP" ; then
+  if echo a | grep -E '(a|b)' > /dev/null 2> /dev/null; then
+    EGREP="grep -E"
+  else
+    EGREP="egrep"
+  fi
+fi
+
 : ${filesuffix=}; export filesuffix
 : ${move=true}; export move
 : ${forcemail=false}; export forcemail
@@ -77,7 +88,7 @@ for file in $files; do
     { $anychange ||
       anychange=`diff $file.sent $file 2>/dev/null |
 	if test ! -f $file.sent ||
-	   egrep '^[<>] (XPASS|FAIL)' >/dev/null; then
+	   $EGREP '^[<>] (XPASS|FAIL)' >/dev/null; then
 	    echo true
 	else
 	    echo false
diff --git a/contrib/warn_summary b/contrib/warn_summary
index d4c8b6cdb19..afa11802ee1 100755
--- a/contrib/warn_summary
+++ b/contrib/warn_summary
@@ -57,7 +57,7 @@ subdirectoryFilter()
   else
     if test "$filter" = nosub ; then
       # Omit all subdirectories.
-      egrep -v '/gcc/(ch|cp|f|fortran|ada|intl|fixinc)/'
+      $EGREP -v '/gcc/(ch|cp|f|fortran|ada|intl|fixinc)/'
     else
       # Pass through only subdir $filter.
       grep "/gcc/$filter/"
@@ -155,6 +155,17 @@ if test -z "$AWK" ; then
   done
 fi
 
+# Prefer "grep -E" which should work with POSIX-conform grep, but fallback
+# to "egrep" (which is deprecated for a long time) if grep does not support
+# -E.
+if test -z "$EGREP" ; then
+  if echo a | grep -E '(a|b)' > /dev/null 2> /dev/null; then
+    EGREP="grep -E"
+  else
+    EGREP="egrep"
+  fi
+fi
+
 # Parse command line arguments.
 while test -n "$1" ; do
  case "$1" in