runtime: stop using sigreturn on openbsd/386

In future releases of OpenBSD, the sigreturn syscall will no longer
exist. As such, stop using sigreturn on openbsd/386 and just return
from the signal trampoline (as we already do for openbsd/amd64 and
openbsd/arm).

Change-Id: Ic4de1795bbfbfb062a685832aea0d597988c6985
Reviewed-on: https://go-review.googlesource.com/23024
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

diff --git a/src/runtime/sys_openbsd_386.s b/src/runtime/sys_openbsd_386.s
index f80a85fb67767b327b534cb5d6481e5d1a4d3d2c..2bb818f456ea2e358160d87c706acdc187636594 100644 (file)
--- a/src/runtime/sys_openbsd_386.s
+++ b/src/runtime/sys_openbsd_386.s
@@ -214,14 +214,6 @@ TEXT runtime·sigtramp(SB),NOSPLIT,$12
        MOVL    context+8(FP), BX
        MOVL    BX, 8(SP)
        CALL    runtime·sigtrampgo(SB)
-
-       // call sigreturn
-       MOVL    context+8(FP), AX
-       MOVL    $0, 0(SP)               // syscall gap
-       MOVL    AX, 4(SP)               // arg 1 - sigcontext
-       MOVL    $103, AX                // sys_sigreturn
-       INT     $0x80
-       MOVL    $0xf1, 0xf1             // crash
        RET
 
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