diff --git a/build/ck.pc.in b/build/ck.pc.in
index 5350c9c..0f1e93b 100644
--- a/build/ck.pc.in
+++ b/build/ck.pc.in
@@ -7,4 +7,4 @@ Description: Toolkit for well-specified design and implementation of concurrent
 URL: http://concurrencykit.org/
 Version: @VERSION@
 Libs: -L${libdir} -lck
-Cflags: -D__@PROFILE@__ -I${includedir} @PC_CFLAGS
+Cflags: -D__@PROFILE@__ -I${includedir} @PC_CFLAGS@