--- gcc-8.3.0/libgo/go/runtime/mem_gccgo.go.old	2018-01-09 01:23:08.000000000 +0000
+++ gcc-8.3.0/libgo/go/runtime/mem_gccgo.go	2019-03-03 05:15:33.010000000 +0000
@@ -16,7 +16,7 @@
 //go:linkname sysFree runtime.sysFree
 
 //extern mmap
-func sysMmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uintptr) unsafe.Pointer
+func sysMmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off int64) unsafe.Pointer
 
 //extern munmap
 func munmap(addr unsafe.Pointer, length uintptr) int32
@@ -41,7 +41,7 @@
 	}
 }
 
-func mmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off uintptr) (unsafe.Pointer, int) {
+func mmap(addr unsafe.Pointer, n uintptr, prot, flags, fd int32, off int64) (unsafe.Pointer, int) {
 	p := sysMmap(addr, n, prot, flags, fd, off)
 	if uintptr(p) == _MAP_FAILED {
 		return nil, errno()
@@ -84,7 +84,7 @@
 	return true
 }
 
-func mmap_fixed(v unsafe.Pointer, n uintptr, prot, flags, fd int32, offset uintptr) (unsafe.Pointer, int) {
+func mmap_fixed(v unsafe.Pointer, n uintptr, prot, flags, fd int32, offset int64) (unsafe.Pointer, int) {
 	p, err := mmap(v, n, prot, flags, fd, offset)
 	// On some systems, mmap ignores v without
 	// MAP_FIXED, so retry if the address space is free.