Index: graphics/darktable/Makefile
===================================================================
--- graphics/darktable/Makefile
+++ graphics/darktable/Makefile
@@ -125,6 +125,10 @@
 CMAKE_ARGS+=	-DCMAKE_POLICY_DEFAULT_CMP0056:STRING=NEW
 .endif
 
+# On at least FreeBSD 9.3-RELEASE, powl(3) is hidden behind the
+# following define. So let's define it to fix the build.
+CFLAGS+=	-D_DECLARE_C99_LDBL_MATH
+
 .if defined(WITH_DEBUG)
 CMAKE_BUILD_TYPE=	RelWithDebInfo
 STRIP=