runtime: reset DF flag after running external code on 386

R=r
CC=golang-dev
https://golang.org/cl/186108

diff --git a/src/pkg/runtime/386/asm.s b/src/pkg/runtime/386/asm.s
index 11ce3f6b6f0f783f1d798cd8d0e5b0948d5086ff..aa0fd95bb40d88beb127a85ddd79a8d0323acf9e 100644 (file)
--- a/src/pkg/runtime/386/asm.s
+++ b/src/pkg/runtime/386/asm.s
@@ -350,6 +350,10 @@ TEXT       runcgo(SB),7,$16
        MOVL    CX, 4(SP)
        MOVL    BX, 0(SP)
        CALL    AX
+       
+       // Back; switch to original stack, re-establish
+       // "DF is clear" invariant.
+       CLD
        MOVL    4(SP), SP
        RET