diff --git a/test/Sema/implicit-builtin-decl.c b/test/Sema/implicit-builtin-decl.c
index 8cdd365..d7ec169 100644
--- a/test/Sema/implicit-builtin-decl.c
+++ b/test/Sema/implicit-builtin-decl.c
@@ -55,3 +55,5 @@
 
 // PR8316
 void longjmp(); // expected-warning{{declaration of built-in function 'longjmp' requires inclusion of the header <setjmp.h>}}
+
+extern float fmaxf(float, float);