diff --git a/test/FrontendC/2008-07-08-FAbsAttributes.c b/test/FrontendC/2008-07-08-FAbsAttributes.c
new file mode 100644
index 00000000000..1eb01dcedbe
--- /dev/null
+++ b/test/FrontendC/2008-07-08-FAbsAttributes.c
@@ -0,0 +1,4 @@
+// RUN: %llvmgcc -S %s -o - | grep readnone
+// PR2520
+#include <math.h>
+double f(double *x, double *y) { return fabs(*x + *y); }