cmd/gc: change interface representation: only pointers in data word

Note that there are various cleanups that can be made if we keep
this change, but I do not want to start making changes that
depend on this one until the 1.4 cycle closes.

Fixes #8405.

LGTM=r
R=golang-codereviews, adg, r, bradfitz
CC=golang-codereviews, iant
https://golang.org/cl/130240043

diff --git a/src/cmd/gc/subr.c b/src/cmd/gc/subr.c
index 325614e6bcf20f30c7e5d816b2601f65b390f033..081c373a889cc4f85d903350ed9305f8746b08d2 100644 (file)
--- a/src/cmd/gc/subr.c
+++ b/src/cmd/gc/subr.c
@@ -3808,7 +3808,7 @@ isdirectiface(Type *t)
        // where the data word can hold a pointer or any
        // non-pointer value no bigger than a pointer.
        enum {
-               IfacePointerOnly = 0,
+               IfacePointerOnly = 1,
        };
 
        if(IfacePointerOnly) {