Problem #1 is I didn't get an email alerting me to this failure. Problem #2 we got these failures. Wed Aug 25 19:11:22 2021 -0700 7a75dbc: PASS Wed Aug 25 19:38:13 2021 -0700 04f903f: PASS Wed Aug 25 19:48:12 2021 -0700 935ab8f: PASS Wed Aug 25 19:50:46 2021 -0700 a0aaea6: PASS Wed Aug 25 21:09:19 2021 -0700 07cdff9: PASS Thu Aug 26 20:24:47 2021 -0700 c90b5de: PASS Thu Aug 26 21:45:27 2021 -0700 a56162c: FAIL Thu Aug 26 22:26:56 2021 -0700 386af0e: FAIL Fri Aug 27 10:26:59 2021 -0700 552db8f: FAIL Fri Aug 27 10:27:04 2021 -0700 b56400f: FAIL It started failing with this commit: https://git.kernel.org/pub/scm/libs/libcap/libcap.git/commit/?id=a56162c6900d203c5ac63a2b41b46cb0c45c645f Curiously, the crash is not consistent [386af0e]: LD_LIBRARY_PATH=../libcap ./compare-cap *** buffer overflow detected ***: terminated SIGABRT: abort PC=0x7fae3e2b218b m=0 sigcode=18446744073709551610 [the next time (386af0e) it looked like this]: LD_LIBRARY_PATH=../libcap ./compare-cap *** buffer overflow detected ***: terminated SIGABRT: abort PC=0x7fea1463e18b m=0 sigcode=18446744073709551610 [the next commit: 552db8f] gcc -O2 -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Dlinux -Wall -Wwrite-strings -Wpointer-arith -Wcast-qual -Wcast-align -Wstrict-prototypes -Wmissing-prototypes -Wnested-externs -Winline -Wshadow -g -fPIC -I/home/runner/work/libcap-testing/libcap-testing/clone/libcap/libcap/../libcap/include/uapi -I/home/runner/work/libcap-testing/libcap-testing/clone/libcap/libcap/../libcap/include cap_test.c cap_alloc.o cap_proc.o cap_extint.o cap_flag.o cap_text.o cap_file.o -o cap_test ./cap_test *** buffer overflow detected ***: terminated make[1]: *** [Makefile:146: test] Aborted (core dumped) make[1]: Leaving directory '/home/runner/work/libcap-testing/libcap-testing/clone/libcap/libcap' make: *** [Makefile:45: test] Error 2 [the last commit: b56400f] make -C libcap test make[1]: Entering directory '/home/runner/work/libcap-testing/libcap-testing/clone/libcap/libcap' gcc -O2 -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Dlinux -Wall -Wwrite-strings -Wpointer-arith -Wcast-qual -Wcast-align -Wstrict-prototypes -Wmissing-prototypes -Wnested-externs -Winline -Wshadow -g -fPIC -I/home/runner/work/libcap-testing/libcap-testing/clone/libcap/libcap/../libcap/include/uapi -I/home/runner/work/libcap-testing/libcap-testing/clone/libcap/libcap/../libcap/include cap_test.c cap_alloc.o cap_proc.o cap_extint.o cap_flag.o cap_text.o cap_file.o -o cap_test ./cap_test *** buffer overflow detected ***: terminated make[1]: *** [Makefile:146: test] Aborted (core dumped)
I think the first two failing commits were because of the bug I introduced. One that I fixed in 552db8f. I added some new test code in 552db8f and that appears to be where the current failure is occurring. Since I can't reproduce this failure on my personal systems, I may have to resort to some debugging commits to track down the problem(s).
OK, so I figured out why I wasn't getting email on the build failure.
A fix (not sure if it is "the" fix), plus some more debugging info: https://git.kernel.org/pub/scm/libs/libcap/libcap.git/commit/?id=de1130dbfe6d4ce99422b11cac147d39448bcd40
Thu Aug 26 20:24:47 2021 -0700 c90b5de: PASS Bugs introduced as a side effect of "fixing" a clang build warning: Thu Aug 26 21:45:27 2021 -0700 a56162c: FAIL Thu Aug 26 22:26:56 2021 -0700 386af0e: FAIL Bug modified after a wave of static analysis fixes, one of which was an partial fix for the bug(s) introduced above: https://git.kernel.org/pub/scm/libs/libcap/libcap.git/commit/?id=552db8f4116df3fad4e4ebf90a9a05a77b9486fd Fri Aug 27 10:26:59 2021 -0700 552db8f: FAIL Fri Aug 27 10:27:04 2021 -0700 b56400f: FAIL Fri Aug 27 13:55:11 2021 -0700 de1130d: FAIL Happened to notice the build failures, and figured out how to fix "the build server" to notify me of failures once more... Instrumentation added [sadly no real insight gained]: https://git.kernel.org/pub/scm/libs/libcap/libcap.git/commit/?id=43365cf01c64b530e7a3d62214247e1aa042414d Fri Aug 27 21:01:46 2021 -0700 43365cf: FAIL Figured out the fix [learned about how to turn on the automated buffer overflow glibc detection code, and then debugged, under gdb, the failing binary]: https://git.kernel.org/pub/scm/libs/libcap/libcap.git/commit/?id=6c38eb78d96a60a9503dc5c89ade67b65778fed9 Sat Aug 28 09:43:51 2021 -0700 6c38eb7: PASS All good.