build: improve compiler version detection portability

POSIX sed doesn't support extended regular expressions, so convert a
call to the basic format. This caused a problem on AIX. Also, use the
detected sed binary name instead of hard-coding one.

diff --git a/m4/curl-compilers.m4 b/m4/curl-compilers.m4
index 0fde2f9455dae35dcefa01f5e547e8dc1e7548a4..3890d536c41b1985d7ee6dba367cb0d9acd5ee09 100644 (file)
--- a/m4/curl-compilers.m4
+++ b/m4/curl-compilers.m4
@@ -185,7 +185,7 @@ AC_DEFUN([CURL_CHECK_COMPILER_GNU_C], [
     compiler_id="GNU_C"
     AC_MSG_CHECKING([compiler version])
     # strip '-suffix' parts, e.g. Ubuntu Windows cross-gcc returns '10-win32'
-    gccver=`$CC -dumpversion | sed -E 's/-.+$//'`
+    gccver=`$CC -dumpversion | "$SED" 's/-.\{1,\}$//'`
     gccvhi=`echo $gccver | cut -d . -f1`
     if echo $gccver | grep -F '.' >/dev/null; then
       gccvlo=`echo $gccver | cut -d . -f2`