• Ian Lance Taylor's avatar
    cmd/cgo, runtime, runtime/cgo: TSAN support for malloc · a5d1a72a
    Ian Lance Taylor authored
    Acquire and release the TSAN synchronization point when calling malloc,
    just as we do when calling any other C function. If we don't do this,
    TSAN will report false positive errors about races calling malloc and
    free.
    
    We used to have a special code path for malloc and free, going through
    the runtime functions cmalloc and cfree. The special code path for cfree
    was no longer used even before this CL. This CL stops using the special
    code path for malloc, because there is no place along that path where we
    could conditionally insert the TSAN synchronization. This CL removes
    the support for the special code path for both functions.
    
    Instead, cgo now automatically generates the malloc function as though
    it were referenced as C.malloc.  We need to automatically generate it
    even if C.malloc is not called, even if malloc and size_t are not
    declared, to support cgo-provided functions like C.CString.
    
    Change-Id: I829854ec0787a80f33fa0a8a0dc2ee1d617830e2
    Reviewed-on: https://go-review.googlesource.com/23260Reviewed-by: 's avatarDmitry Vyukov <dvyukov@google.com>
    Run-TryBot: Ian Lance Taylor <iant@golang.org>
    TryBot-Result: Gobot Gobot <gobot@golang.org>
    Reviewed-by: 's avatarAustin Clements <austin@google.com>
    a5d1a72a
cgocall.go 19.3 KB