diff options
| author | Russ Cox <rsc@golang.org> | 2014-10-07 11:06:51 -0400 |
|---|---|---|
| committer | Russ Cox <rsc@golang.org> | 2014-10-07 11:06:51 -0400 |
| commit | 44ae5998770a185d1f8518b6917e1c094bc62a19 (patch) | |
| tree | 272222847117acc2ce64d1a80d36777e72fb975b /src/reflect | |
| parent | 049be2f16a585e45be4d8fe17660a537934488ee (diff) | |
| download | go-44ae5998770a185d1f8518b6917e1c094bc62a19.tar.gz | |
runtime: remove type-punning for Type.gc[0], gc[1]
Depending on flags&KindGCProg,
gc[0] and gc[1] are either pointers or inlined bitmap bits.
That's not compatible with a precise garbage collector:
it needs to be always pointers or never pointers.
Change the inlined bitmap case to store a pointer to an
out-of-line bitmap in gc[0]. The out-of-line bitmaps are
dedup'ed, so that for example all pointer types share the
same out-of-line bitmap.
Fixes issue 8864.
LGTM=r
R=golang-codereviews, dvyukov, r
CC=golang-codereviews, iant, khr, rlh
https://codereview.appspot.com/155820043
Diffstat (limited to 'src/reflect')
| -rw-r--r-- | src/reflect/type.go | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/src/reflect/type.go b/src/reflect/type.go index f099546d2..a36c0ba60 100644 --- a/src/reflect/type.go +++ b/src/reflect/type.go @@ -1523,8 +1523,8 @@ func (gc *gcProg) appendProg(t *rtype) { // The program is stored in t.gc[0], skip unroll flag. prog = (*[1 << 30]byte)(unsafe.Pointer(t.gc[0]))[1:] } else { - // The mask is embed directly in t.gc. - prog = (*[1 << 30]byte)(unsafe.Pointer(&t.gc[0]))[:] + // The mask is linked directly in t.gc. + prog = (*[2 * ptrSize]byte)(unsafe.Pointer(t.gc[0]))[:] } for i := uintptr(0); i < nptr; i++ { gc.appendWord(extractGCWord(prog, i)) |