Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx> writes: > Refactor tr2_dst_try_uds_connect() to avoid a gcc warning[1] that > appears under -O3 (but not -O2). This makes the build pass under > DEVELOPER=1 without needing a DEVOPTS=no-error. > > This can be reproduced with GCC Debian 8.3.0-6, but not e.g. with > clang 7.0.1-8+deb10u2. We've had this warning since > ee4512ed481 (trace2: create new combined trace facility, 2019-02-22). > > As noted in [2] this warning happens because the compiler doesn't > assume that errno must be non-zero after a failed syscall. Let's work > around it as suggested in that analysis. We now return -1 ourselves on > error, and save away the value of errno in a variable the caller > passes in. > > 1. > > trace2/tr2_dst.c: In function ‘tr2_dst_get_trace_fd.part.5’: > trace2/tr2_dst.c:296:10: warning: ‘fd’ may be used uninitialized in this function [-Wmaybe-uninitialized] > dst->fd = fd; > ~~~~~~~~^~~~ > trace2/tr2_dst.c:229:6: note: ‘fd’ was declared here > int fd; > ^~ > 2. https://lore.kernel.org/git/20200404142131.GA679473@xxxxxxxxxxxxxxxxxxxxxxx/ > --- > trace2/tr2_dst.c | 27 +++++++++++++++------------ > 1 file changed, 15 insertions(+), 12 deletions(-) What's the concensus if any on this topic? In any case, this needs to be signed off before it gets carved into our history. Thanks.
