Re: [Qemu-devel] test-qapi-visit causes clang -fsanitize=undefined warning

[Peter Maydell]

On 10 March 2014 13:36, Markus Armbruster <address@hidden> wrote:
> Peter Maydell <address@hidden> writes:
> Turns out my clang installation doesn't support -fsanitize=undefined: it
> lacks libclang_rt.san-x86_64.a.
>
> Test works fine without -fsanitize=undefined.  I set a breakpoint on
> visit_type_UserDefA_fields, and there's no null pointer to be found.

Yes, there is. This is gdb on a gcc-compiled version of
the test:

/visitor/input-strict/fail/union-flat:
Breakpoint 1, visit_type_UserDefA_fields (m=0x5555557a8ed0,
obj=0x5555557a8d88, errp=0x7fffffffdfb0)
    at tests/test-qapi-visit.c:460
460     {
(gdb) print *obj
$3 = (UserDefA *) 0x0
(gdb) bt
#0  visit_type_UserDefA_fields (m=0x5555557a8ed0, obj=0x5555557a8d88,
errp=0x7fffffffdfb0)
    at tests/test-qapi-visit.c:460
#1  0x000055555555b2a2 in visit_type_UserDefFlatUnion
(m=0x5555557a8ed0, obj=0x7fffffffdfd8, name=0x0, errp=0x0)
    at tests/test-qapi-visit.c:654
#2  0x0000555555558c0b in qapi_free_UserDefFlatUnion
(obj=0x5555557a8d80) at tests/test-qapi-types.c:368
#3  0x000055555555cc47 in test_validate_fail_union_flat
(data=0x5555557a8de0, unused=0x7fffffffe3f0)
    at 
/home/petmay01/linaro/qemu-from-laptop/qemu/tests/test-qmp-input-strict.c:241

*obj is NULL, which is what clang is complaining about.

thanks
-- PMM