[gimp] app: add compiler info in `gimp -v`.

[Jehan Pagès <jehanp src gnome org>]

commit 2c19ea21457b5e79b1c8621ed79337f07c273143
Author: Jehan <jehan girinstud io>
Date:   Sun Sep 10 01:20:13 2017 +0200

    app: add compiler info in `gimp -v`.

 app/Makefile.am |    1 +
 app/version.c   |    1 +
 configure.ac    |   16 ++++++++++++++++
 3 files changed, 18 insertions(+), 0 deletions(-)
---
diff --git a/app/Makefile.am b/app/Makefile.am
index 97807cb..59591e9 100644
--- a/app/Makefile.am
+++ b/app/Makefile.am
@@ -115,6 +115,7 @@ AM_CPPFLAGS = \
        -DGIMP_USER_VERSION=\"$(GIMP_USER_VERSION)\"            \
        -DG_LOG_DOMAIN=\"Gimp\"         \
        -DGIMP_APP_GLUE_COMPILATION     \
+       -DCC_VERSION=\""$(CC_VERSION)"\" \
        -I$(top_srcdir)                 \
        $(GTK_CFLAGS)                   \
        $(PANGOCAIRO_CFLAGS)            \
diff --git a/app/version.c b/app/version.c
index 0a54217..de439bc 100644
--- a/app/version.c
+++ b/app/version.c
@@ -142,6 +142,7 @@ gimp_version_show (gboolean be_verbose)
     {
       g_print ("git-describe: %s", GIMP_GIT_VERSION);
       g_print ("\n");
+      g_print ("C compiler:\n%s", CC_VERSION);
 
       g_print ("\n");
       gimp_show_library_versions ();
diff --git a/configure.ac b/configure.ac
index dcff8d8..33665f0 100644
--- a/configure.ac
+++ b/configure.ac
@@ -539,7 +539,23 @@ WARNING: GCC 7.2.0 has a serious bug affecting GEGL/GIMP. We advise
          further versions are fine).
          See https://bugzilla.gnome.org/show_bug.cgi?id=787222";
   fi
+  # For GCC, use -v which has more information than --version.
+  CC_VERSION="\\\\t`$CC -v 2>&1 | sed -e 's/$/\\\\n\\\\t/g' | tr -d '\n'`"
+else
+  # This is the list of common options used by autotools to check
+  # versions for various compilers.
+  CC_VERSION="\\\\t`$CC --version 2>&1 | sed -e 's/$/\\\\n\\\\t/g' | tr -d '\n'`"
+  if test $? != 0; then
+    CC_VERSION="\\\\t`$CC -v 2>&1` | sed -e 's/$/\\\\n\\\\t/g' | tr -d '\n'"
+    if test $? != 0; then
+      CC_VERSION="\\\\t`$CC -V 2>&1` | sed -e 's/$/\\\\n\\\\t/g' | tr -d '\n'"
+      if test $? != 0; then
+        CC_VERSION="\\\\t`$CC -qversion 2>&1` | sed -e 's/$/\\\\n\\\\t/g' | tr -d '\n'"
+      fi
+    fi
+  fi
 fi
+AC_SUBST(CC_VERSION)
 
 AC_HEADER_STDC
 AC_HEADER_SYS_WAIT