diff options
Diffstat (limited to 'src/runtime/mbitmap.go')
| -rw-r--r-- | src/runtime/mbitmap.go | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/src/runtime/mbitmap.go b/src/runtime/mbitmap.go index daf1fcfbc0..3330ddd62e 100644 --- a/src/runtime/mbitmap.go +++ b/src/runtime/mbitmap.go @@ -417,6 +417,15 @@ func findObject(p, refBase, refOff uintptr) (base uintptr, s *mspan, objIndex ui return } +// verifyNotInHeapPtr reports whether converting the not-in-heap pointer into a unsafe.Pointer is ok. +//go:linkname reflect_verifyNotInHeapPtr reflect.verifyNotInHeapPtr +func reflect_verifyNotInHeapPtr(p uintptr) bool { + // Conversion to a pointer is ok as long as findObject above does not call badPointer. + // Since we're already promised that p doesn't point into the heap, just disallow heap + // pointers and the special clobbered pointer. + return spanOf(p) == nil && p != clobberdeadPtr +} + // next returns the heapBits describing the next pointer-sized word in memory. // That is, if h describes address p, h.next() describes p+ptrSize. // Note that next does not modify h. The caller must record the result. |