From e0ebc75df24dbfaabb4e97e7de1ab4d4cd36abf2 Mon Sep 17 00:00:00 2001
From: Ayke van Laethem <aykevanlaethem@gmail.com>
Date: Mon, 16 Sep 2019 14:11:53 +0200
Subject: [PATCH] runtime: implement memcpy

A call to memcpy is sometimes created by the compiler, for example when
compiling with -opt=s or opt=2.
---
 src/runtime/runtime_cortexm.go | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/runtime/runtime_cortexm.go b/src/runtime/runtime_cortexm.go
index 55d41d25..2622b67a 100644
--- a/src/runtime/runtime_cortexm.go
+++ b/src/runtime/runtime_cortexm.go
@@ -132,3 +132,9 @@ func libc_memset(ptr unsafe.Pointer, c byte, size uintptr) {
 func libc_memmove(dst, src unsafe.Pointer, size uintptr) {
 	memmove(dst, src, size)
 }
+
+// Implement memcpy for LLVM and compiler-rt.
+//go:export memcpy
+func libc_memcpy(dst, src unsafe.Pointer, size uintptr) {
+	memcpy(dst, src, size)
+}