-g3 is a GNU gcc specific flag. We are using the gnu compiler only if

the vendor is gnu. Otherwise, if GCC is set for all the compilers who
impersonate gcc like icc.

This commit was SVN r9217.

config/ompi_setup_cc.m4

@@ -48,7 +48,7 @@ AC_DEFUN([OMPI_SETUP_CC],[
 
     # Do we want debugging?
     if test "$WANT_DEBUG" = "1"; then
-        if test "$GCC" = yes; then
+        if test "$ompi_c_vendor" = "gnu"; then
             CFLAGS="$CFLAGS -g3"
         else
             CFLAGS="$CFLAGS -g"