syscall: correct code for cover cmd

Fixes #10378

This is clumsy, but currently cover tool fails as:

$ go test -run=none -cover syscall
syscall_linux_amd64.go:15: can only use //go:noescape with external func implementations
FAIL	syscall [build failed]

This happens because cover tool mishandles //go: comments.
r and gri said that fixing cover is infeasible due to go/ast limitations.

So at least fix the offending code so that coverage works.
This come up in context of coverage-guided fuzzing which works best
with program-wide coverage.

Change-Id: I142e5774c9f326ed38cb202693bd4edae93879ba
Reviewed-on: https://go-review.googlesource.com/8723
Reviewed-by: Rob Pike <r@golang.org>

diff --git a/src/syscall/syscall_linux_amd64.go b/src/syscall/syscall_linux_amd64.go
index 4111c075e81c7602577c9cc7c785070764084707..fad9c325809dc2f81bd51a0b8d9c9f843090ef64 100644 (file)
--- a/src/syscall/syscall_linux_amd64.go
+++ b/src/syscall/syscall_linux_amd64.go
@@ -57,8 +57,6 @@ const _SYS_dup = SYS_DUP2
 //sys  sendmsg(s int, msg *Msghdr, flags int) (n int, err error)
 //sys  mmap(addr uintptr, length uintptr, prot int, flags int, fd int, offset int64) (xaddr uintptr, err error)
 
-func Getpagesize() int { return 4096 }
-
 //go:noescape
 func gettimeofday(tv *Timeval) (err Errno)
 
@@ -70,6 +68,8 @@ func Gettimeofday(tv *Timeval) (err error) {
        return nil
 }
 
+func Getpagesize() int { return 4096 }
+
 func Time(t *Time_t) (tt Time_t, err error) {
        var tv Timeval
        errno := gettimeofday(&tv)