diff --git a/build/php.m4 b/build/php.m4
index 176d4d41447..e45b22b7665 100644
--- a/build/php.m4
+++ b/build/php.m4
@@ -2533,3 +2533,15 @@ AS_VAR_IF([php_var], [yes],
     [Define to 1 if the compiler supports the '$1' variable attribute.])])
 AS_VAR_POPDEF([php_var])
 ])
+
+dnl
+dnl PHP_REMOVE_OPTIMIZATION_FLAGS
+dnl
+dnl Removes known compiler optimization flags like -O, -O0, -O1, ..., -Ofast
+dnl from CFLAGS and CXXFLAGS.
+dnl
+AC_DEFUN([PHP_REMOVE_OPTIMIZATION_FLAGS], [
+  sed_script='s/\([[\t ]]\|^\)-O\([[0-9gsz]]\|fast\|\)\([[\t ]]\|$\)/\1/g'
+  CFLAGS=$(echo "$CFLAGS" | $SED -e "$sed_script")
+  CXXFLAGS=$(echo "$CXXFLAGS" | $SED -e "$sed_script")
+])
diff --git a/configure.ac b/configure.ac
index c7e36ca70c9..c728970129f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -785,11 +785,7 @@ AS_VAR_IF([PHP_GCOV], [yes], [
   PHP_ADD_MAKEFILE_FRAGMENT([$abs_srcdir/build/Makefile.gcov], [$abs_srcdir])
 
   dnl Remove all optimization flags from CFLAGS.
-  changequote({,})
-  dnl Discard known '-O...' flags, including just '-O', but do not remove only '-O' in '-Ounknown'
-  CFLAGS=$(echo "$CFLAGS" | $SED -e 's/-O\([0-9gsz]\|fast\|\)\([\t ]\|$\)//g')
-  CXXFLAGS=$(echo "$CXXFLAGS" | $SED -e 's/-O\([0-9gsz]\|fast\|\)\([\t ]\|$\)//g')
-  changequote([,])
+  PHP_REMOVE_OPTIMIZATION_FLAGS
 
   dnl Add the special gcc flags.
   CFLAGS="$CFLAGS -O0 -fprofile-arcs -ftest-coverage"
@@ -806,11 +802,7 @@ PHP_ARG_ENABLE([debug],
 AS_VAR_IF([PHP_DEBUG], [yes], [
   PHP_DEBUG=1
   ZEND_DEBUG=yes
-  changequote({,})
-  dnl Discard known '-O...' flags, including just '-O', but do not remove only '-O' in '-Ounknown'
-  CFLAGS=$(echo "$CFLAGS" | $SED -e 's/-O\([0-9gsz]\|fast\|\)\([\t ]\|$\)//g')
-  CXXFLAGS=$(echo "$CXXFLAGS" | $SED -e 's/-O\([0-9gsz]\|fast\|\)\([\t ]\|$\)//g')
-  changequote([,])
+  PHP_REMOVE_OPTIMIZATION_FLAGS
   dnl Add -O0 only if GCC or ICC is used.
   if test "$GCC" = "yes" || test "$ICC" = "yes"; then
     CFLAGS="$CFLAGS -O0"
diff --git a/scripts/phpize.m4 b/scripts/phpize.m4
index e59a1c03a57..be7065b786d 100644
--- a/scripts/phpize.m4
+++ b/scripts/phpize.m4
@@ -104,11 +104,7 @@ dnl Discard optimization flags when debugging is enabled.
 AS_VAR_IF([PHP_DEBUG], [yes], [
   PHP_DEBUG=1
   ZEND_DEBUG=yes
-  changequote({,})
-  dnl Discard known '-O...' flags, including just '-O', but do not remove only '-O' in '-Ounknown'
-  CFLAGS=$(echo "$CFLAGS" | $SED -e 's/-O\([0-9gsz]\|fast\|\)\([\t ]\|$\)//g')
-  CXXFLAGS=$(echo "$CXXFLAGS" | $SED -e 's/-O\([0-9gsz]\|fast\|\)\([\t ]\|$\)//g')
-  changequote([,])
+  PHP_REMOVE_OPTIMIZATION_FLAGS
   dnl Add -O0 only if GCC or ICC is used.
   if test "$GCC" = "yes" || test "$ICC" = "yes"; then
     CFLAGS="$CFLAGS -O0"