cmd/cgo: better handling for '.' in pkgpath for gccgo

Update gccgoPkgpathToSymbolNew() to bring it into conformance
with the way that gccgo now handles packagepaths with embedded
dots (see CL 200838). See also https://gcc.gnu.org/PR61880, a
related bug.

Updates #35623.

Change-Id: I32f064320b9af387fc17771530c745a9e3003c20
Reviewed-on: https://go-review.googlesource.com/c/go/+/207957
Run-TryBot: Than McIntosh <thanm@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

diff --git a/src/cmd/cgo/out.go b/src/cmd/cgo/out.go
index 6bee9b1909f42c5cd2f5a6867ea548eb80641f31..e32a3a607bbafa2e6a283ee1764f416104b92cf8 100644 (file)
--- a/src/cmd/cgo/out.go
+++ b/src/cmd/cgo/out.go
@@ -1313,8 +1313,10 @@ func gccgoPkgpathToSymbolNew(ppath string) string {
        for _, c := range []byte(ppath) {
                switch {
                case 'A' <= c && c <= 'Z', 'a' <= c && c <= 'z',
-                       '0' <= c && c <= '9', c == '_', c == '.':
+                       '0' <= c && c <= '9', c == '_':
                        bsl = append(bsl, c)
+               case c == '.':
+                       bsl = append(bsl, ".x2e"...)
                default:
                        changed = true
                        encbytes := []byte(fmt.Sprintf("..z%02x", c))