While I was searching for other errors in make check, I set up a few machines on top of virtualbox to compile and check qemu master, and make check failed in a few of them when compiling with clang (< 3.5) (gcc works perfectly). I found two errors in acpi/tcg test in tests/bios-tables-test.c
--- Error 1 --- Log (sometimes the first, sometimes the second): /i386/acpi/tcg: [I 1421766735.433486] OPENED {"QMP": {"version": {"qemu": {"micro": 50, "minor": 2, "major": 2}, "package": ""}, "capabilities": []}}{"execute": "qmp_capabilities"} {"return": {}}[R +0.027951] readb 0x7c10 [S +0.028104] OK 0x0000000000000000 [R +0.028267] readb 0x7c11 [S +0.028290] OK 0x0000000000000000 Broken pipe /i386/acpi/tcg: [I 1421766738.230861] OPENED {"QMP": {"version": {"qemu": {"micro": 50, "minor": 2, "major": 2}, "package": ""}, "capabilities": []}}{"execute": "qmp_capabilities"} {"return": {}}Broken pipe Platforms it failed (all on top of Virtualbox): - Ubuntu 14.04.1 Linux 3.13.0 i386 Clang 3.4. Had to configure with -disable-werror because of "clang: error: argument unused during compilation: '-nopie'". --- Error 2 --- Log: /i386/acpi/tcg: [I 1421845839.538638] OPENED {"QMP": {"version": {"qemu": {"micro": 50, "minor": 2, "major": 2}, "package": ""}, "capabilities": []}}{"execute": "qmp_capabilities"} {"return": {}}[R +0.025626] readb 0x7c10 [S +0.025858] OK 0x0000000000000000 [R +0.026287] readb 0x7c11 [S +0.026506] OK 0x0000000000000000 /home/markmb/qemu/cpu-exec.c:550:&: Object 0xb84dc1a0 is not an instance of type 8�@�x�@�h@�h@� Platforms it failed (all on top of Virtualbox): - Debian 7.8.0 Linux 3.2.0 i386 Clang 3.0-6 - Ubuntu 12.04 Linux 3.13.0 i386 Clang 3.0-6 I tried in other setups with Clang 3.5 and no errors. I tried with x86_64 virtualized systems and no errors. I tried in a native x86_64 (host for all tests. Debian 7 Linux 3.2.65 clang 3.0-6) and did not fail. I could not test in a native i386. Maybe it's not important as it just happens with old clangs, or maybe you want to give it a look. Thanks Marc