On Fri, 02 Aug 2019 at 11:41:05 +0100, Iain Lane wrote: > For the record: at Debconf doko suggested to me that a way to start > debugging this from the GCC end would be to produce one working and one > "broken" build of the same version of glib2.0, and then copy object > files from the broken to the working one until that too becomes broken. > That sounded long / tedious / fiddly so we didn't manage to get round to > doing it while we were both there, unfortunately.
This is not straightforward in the Meson/Ninja build system, but what I could do was to hack build.ninja to compile different files with different compilers, which narrowed it down to gtestutils.c (?!). Playing with #pragma GCC optimize ("O1") and #pragma GCC optimize ("O2") I was able to narrow it down further, to this: If you compile test_run_seed() with -O1, and the rest of gtestutils.c with -O2, the clutter test hangs. (But I need to test that minimal change in a clean build to make sure that's really true and not being affected by other hacks.) smcv