define FIRM_BUILD_DLL so symbols are actually exported

[r27567]

diff --git a/configure.ac b/configure.ac
index 91b68f0..a30ad0b 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -38,6 +38,7 @@ AC_SUBST(libfirm_conf_env)
 
 dnl enable visibility hidden
 CFLAGS="-fvisibility=hidden"
+AC_DEFINE([FIRM_BUILD_DLL], [], [Define when firm library is built])
 
 dnl Package options
 dnl ===============