diff --git a/src/gui/widget/Makefile.am b/src/gui/widget/Makefile.am
index 33dd69179..d119ced33 100644
--- a/src/gui/widget/Makefile.am
+++ b/src/gui/widget/Makefile.am
@@ -1,4 +1,4 @@
-AM_CPPFLAGS = -fno-rtti -fno-exceptions
+AM_CPPFLAGS = -fno-rtti -fno-exceptions -D__STDC_FORMAT_MACROS
 
 AM_CPPFLAGS += \
 	-I$(top_builddir) \