vala.m4: honour CC, CPPFLAGS, CFLAGS, LDFLAGS

These variables may be set to values that are required to build
executables.  Make sure we honour them from vala.m4 when attempting to
check for packages.

https://bugzilla.gnome.org/show_bug.cgi?id=724176

diff --git a/vala.m4 b/vala.m4
index 79c32a14a1efc643eecd48d3fdcf99113343b5d2..4fc0740c22cf162d87285fb74826f9a85eeb76a0 100644 (file)
--- a/vala.m4
+++ b/vala.m4
@@ -29,7 +29,7 @@ AC_DEFUN([_VALA_CHECK_COMPILE_WITH_ARGS],
 void main(){}
 _ACEOF
 
-  AS_IF([vala_error=`$VALAC $1 -q -o conftest$ac_exeext conftest.vala 2>&1`],
+  AS_IF([vala_error=`$VALAC $1 -q --cc="${CC} ${CPPFLAGS} ${CFLAGS} ${LDFLAGS}" -o conftest$ac_exeext conftest.vala 2>&1`],
         [$2], [$3])
 ])