diff --git a/cpu/cpu_gc_x86.go b/cpu/cpu_gc_x86.go
index 3298a87e..fa7cdb9b 100644
--- a/cpu/cpu_gc_x86.go
+++ b/cpu/cpu_gc_x86.go
@@ -15,7 +15,3 @@ func cpuid(eaxArg, ecxArg uint32) (eax, ebx, ecx, edx uint32)
 // xgetbv with ecx = 0 is implemented in cpu_x86.s for gc compiler
 // and in cpu_gccgo.c for gccgo.
 func xgetbv() (eax, edx uint32)
-
-// darwinSupportsAVX512 is implemented in cpu_x86.s for gc compiler
-// and in cpu_gccgo_x86.go for gccgo.
-func darwinSupportsAVX512() bool