diff --git a/libgcc/libgcc2.c b/libgcc/libgcc2.c
index 3fcb85c5b92e727f95f9936e09bf04b42ea85ddc..27959a6e0f25f8b7ab533489664bb00d9b1ad99e 100644
--- a/libgcc/libgcc2.c
+++ b/libgcc/libgcc2.c
@@ -2673,6 +2673,7 @@ NAME (TYPE x, int m)
 #define isfinite(x)	__builtin_isfinite (x)
 #define isinf(x)	__builtin_isinf (x)
 
+#undef INFINITY
 #define INFINITY	CONCAT2(__builtin_huge_val, CEXT) ()
 #define I		1i