syscall: add missing type conversion

The gofrontend incorrectly accepted code that was missing a type conversion.
The test case for this is bug518.go in https://go.dev/cl/536537.
Future CLs in this series will detect the type error.

Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/536638

1 files changed, 1 insertions, 1 deletions

diff --git a/libgo/go/syscall/errstr.go b/libgo/go/syscall/errstr.go
index 9f688e2..02f228a 100644
--- a/libgo/go/syscall/errstr.go
+++ b/libgo/go/syscall/errstr.go
@@ -24,7 +24,7 @@ func Errstr(errnum int) string {
 			}
 			return string(b[:i])
 		}
-		if errno != ERANGE {
+		if Errno(errno) != ERANGE {
 			return "strerror_r failure"
 		}
 	}