configure: Introduce CLANG variable

Gbp-Pq: Name configure-clang-variable.patch

diff --git a/configure.ac b/configure.ac
index ba36ef90fa1a03892e65947d2ac215c6f1f7e7c1..a8e7dcdf25059a2b36453b53b47e7c228a4bcb38 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -38,6 +38,15 @@
 
     AC_SUBST([CLANG])
 
+    AC_ARG_WITH([clang],
+                [CLANG compiler],
+                [CLANG="$withval"],
+                [AS_IF([test "$compiler" = clang],
+                       [CLANG="$CC"],
+                       [AC_PATH_PROG([CLANG],[clang])])])
+
+    AC_SUBST([CLANG])
+
     case "$compiler" in
         clang)
             CLANG_CFLAGS="-Wextra -Werror-implicit-function-declaration -Wno-error=unused-command-line-argument"