<table border="1" cellspacing="0" cellpadding="8">
    <tr>
        <th>Issue</th>
        <td>
            <a href=https://github.com/llvm/llvm-project/issues/108957>108957</a>
        </td>
    </tr>

    <tr>
        <th>Summary</th>
        <td>
            [libc++] sys_info.zdump.pass.cpp fails on `%z` format with tzdata 2024b
        </td>
    </tr>

    <tr>
      <th>Labels</th>
      <td>
            libc++
      </td>
    </tr>

    <tr>
      <th>Assignees</th>
      <td>
      </td>
    </tr>

    <tr>
      <th>Reporter</th>
      <td>
          mgorny
      </td>
    </tr>
</table>

<pre>
    ```
FAIL: llvm-libc++-shared.cfg.in :: std/time/time.zone/time.zone.timezone/time.zone.members/sys_info.zdump.pass.cpp (8335 of 9747)
******************** TEST 'llvm-libc++-shared.cfg.in :: std/time/time.zone/time.zone.timezone/time.zone.members/sys_info.zdump.pass.cpp' FAILED ********************
Exit Code: 250

Command Output (stdout):
--
# COMPILED WITH
/usr/lib/ccache/bin/i686-pc-linux-gnu-clang++ /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/libcxx/test/std/time/time.zone/time.zone.timezone/time.zone.members/sys_info.zdump.pass.cpp -pthread --target=i686-pc-linux-gnu -nostdinc++ -I /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/libcxx/test-suite-install/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/libcxx/test-suite-install/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/libcxx/test/support -std=c++26 -Werror -Wall -Wctad-maybe-unsupported -Wextra -Wshadow -Wundef -Wunused-template -Wno-unused-command-line-argument -Wno-attributes -Wno-pessimizing-move -Wno-noexcept-type -Wno-atomic-alignment -Wno-reserved-module-identifier -Wdeprecated-copy -Wdeprecated-copy-dtor -Wno-user-defined-literals -Wno-tautological-compare -Wsign-compare -Wunused-variable -Wunused-parameter -Wunreachable-code -Wno-unused-local-typedef -Wno-local-type-template-args -Wno-c++11-extensions -Wno-unknown-pragmas -Wno-pass-failed -Wno-mismatched-new-delete -Wno-redundant-move -Wno-self-move -D_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER -D_LIBCPP_ENABLE_EXPERIMENTAL -D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_NONE -Werror=thread-safety -Wuser-defined-warnings  -lc++experimental -nostdlib++ -L /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/libcxx/test-suite-install/lib -Wl,-rpath,/var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/libcxx/test-suite-install/lib -lc++ -latomic -o /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/test/std/time/time.zone/time.zone.timezone/time.zone.members/Output/sys_info.zdump.pass.cpp.dir/t.tmp.exe
# executed command: /usr/lib/ccache/bin/i686-pc-linux-gnu-clang++ /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/libcxx/test/std/time/time.zone/time.zone.timezone/time.zone.members/sys_info.zdump.pass.cpp -pthread --target=i686-pc-linux-gnu -nostdinc++ -I /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/libcxx/test-suite-install/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/libcxx/test-suite-install/include/c++/v1 -I /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/libcxx/test/support -std=c++26 -Werror -Wall -Wctad-maybe-unsupported -Wextra -Wshadow -Wundef -Wunused-template -Wno-unused-command-line-argument -Wno-attributes -Wno-pessimizing-move -Wno-noexcept-type -Wno-atomic-alignment -Wno-reserved-module-identifier -Wdeprecated-copy -Wdeprecated-copy-dtor -Wno-user-defined-literals -Wno-tautological-compare -Wsign-compare -Wunused-variable -Wunused-parameter -Wunreachable-code -Wno-unused-local-typedef -Wno-local-type-template-args -Wno-c++11-extensions -Wno-unknown-pragmas -Wno-pass-failed -Wno-mismatched-new-delete -Wno-redundant-move -Wno-self-move -D_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER -D_LIBCPP_ENABLE_EXPERIMENTAL -D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_NONE -Werror=thread-safety -Wuser-defined-warnings -lc++experimental -nostdlib++ -L /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/libcxx/test-suite-install/lib -Wl,-rpath,/var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/libcxx/test-suite-install/lib -lc++ -latomic -o /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/test/std/time/time.zone/time.zone.timezone/time.zone.members/Output/sys_info.zdump.pass.cpp.dir/t.tmp.exe
# EXECUTED AS
/usr/bin/python3.13 /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/libcxx/utils/run.py --execdir /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/test/std/time/time.zone/time.zone.timezone/time.zone.members/Output/sys_info.zdump.pass.cpp.dir -- /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/test/std/time/time.zone/time.zone.timezone/time.zone.members/Output/sys_info.zdump.pass.cpp.dir/t.tmp.exe
# executed command: /usr/bin/python3.13 /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/libcxx/utils/run.py --execdir /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/test/std/time/time.zone/time.zone.timezone/time.zone.members/Output/sys_info.zdump.pass.cpp.dir -- /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/runtimes_build-abi_x86_32.x86/test/std/time/time.zone/time.zone.timezone/time.zone.members/Output/sys_info.zdump.pass.cpp.dir/t.tmp.exe
# .---command stderr------------
# | Assertion failure: libcxx.str() == zdump.str() /var/tmp/portage/sys-libs/libcxx-20.0.0_pre20240917/work/libcxx/test/std/time/time.zone/time.zone.timezone/time.zone.members/sys_info.zdump.pass.cpp 123
# | 
# | TZ=Africa/Bissau
# | libc++
# | Africa/Bissau  Mon Jan  1 00:59:59 1912 UT = Sun Dec 31 23:57:39 1911 LMT isdst=0 gmtoff=-3740
# | Africa/Bissau  Mon Jan  1 01:00:00 1912 UT = Mon Jan  1 00:00:00 1912 %z isdst=0 gmtoff=-3600
# | Africa/Bissau  Wed Jan  1 00:59:59 1975 UT = Tue Dec 31 23:59:59 1974 %z isdst=0 gmtoff=-3600
# | Africa/Bissau  Wed Jan  1 01:00:00 1975 UT = Wed Jan  1 01:00:00 1975 GMT isdst=0 gmtoff=0
# | |
# | 
# | zdump
# | Africa/Bissau  Mon Jan 1 00:59:59 1912 UT = Sun Dec 31 23:57:39 1911 LMT isdst=0 gmtoff=-3740
# | Africa/Bissau  Mon Jan  1 01:00:00 1912 UT = Mon Jan  1 00:00:00 1912 -01 isdst=0 gmtoff=-3600
# | Africa/Bissau  Wed Jan  1 00:59:59 1975 UT = Tue Dec 31 23:59:59 1974 -01 isdst=0 gmtoff=-3600
# | Africa/Bissau  Wed Jan 1 01:00:00 1975 UT = Wed Jan  1 01:00:00 1975 GMT isdst=0 gmtoff=0
# | |
# `-----------------------------
# error: command failed with exit status: 250

--

********************
```

Note that `%z` doesn't seem to be expanded. This is on 41f1b467a29d2ca4e35df37c3aa79a0a8c04bc4f.
</pre>
<img width="1px" height="1px" alt="" src="http://email.email.llvm.org/o/eJzsWVtz4jgW_jXiRSWXLQGGBx5IDNPZyq06TDG7L5RsHYN2ZMklyQnJr9-SbTqQvuxuT3ZmehaKsrE4OpfvHB99trhzcqsBZmh0gUbZgDd-Z-ys2hqrnwe5Ec8zNI77b5yheL6cX10jNsdKPVZEybxA9ALRC-J23IKIinIbSY0Rmwch5wWiSy8r6E_Ri9Env6Pw67PBCqocrEN06Z7dRurSRC-iqeqo5s5FRV1jRCcTxkbYlHiaDlNEp517iH7_F68WDyuMaPrHxoZoigPKiwz_lmg6PBZ76fGlERBcpqM-id3x0lQV1wLfNb5ufIDUeWEaH8BkvQwhB1wZvry7uW_dWl-tPhyGl42ziC6VzBFdFgUvdiHcXGpEl3I8GZO6IErqZk-2uiGF4nrboYoRXT7yMNdXNaLL2ljPt9DhEtB3ndpivyc0juIo3tQWaEyH8TRJEV0-GfvrJ5GgBpwPs_9nNUdqv7PABSbEc7sFj1j2WYiYaOO8kLovHkyu3itS2-jgrtvkjVSC8Fxu9pPxhtFoPxm_RYK4RnogUjvPlQrJ0IVqRLDaexa8Sv5_3PusTpo6qMIkFAzLeqt0jMkarDUWkzVXCpN14bkgFX_OgTS6nwUiiO295Zis3Y4L84TJutECyvbcOBDEQ1Ur7gGTtTakHyy6my4UDBBut00F2ncS3Hsr88aD665rcE5W8kXqLanMY69HG9gXUHvin2s4TDSVLAhXcqtf1VlwYB9BkMqIRgGRArSXpYQQmoDaQsF961H9_PkIEb7FIHjuwBIBpdQQ_PZguepd9LzxRpmtLLgKodXcBp_ConJ02Yf-yK3kuToaqbnlFfjWo0Zb4MUuCJDCiFPUlAkGQsQdwtocDX0COuDZO9anM0kI7D1oJ412B42_avOkSW35tuIHqLlzpORStYnVhlTSVdwXOxBEwxMRoOCQSAui0YJrf5QUB6rsL7PN9dXF5f395sP8YXN7t7n_OP_pZr55-PvDanGz-bCYZ4uPR1KL2_nF9WKz-OV-8fHqZnG7ml-f6PiYLW6vbn_a3NxlC8S-8sfm9u52cShcxLKuTxHHS_AhtycZfOJWS711GBPVwwT7GqwMpcNV38Daht41sOs_R4dQMsdkrRC9JLbmfofo5Z_HL_Wp3avubsTE_F6wvdvC1xGBr6-AkZBtNJGv6gj28EoNYA9FE7pi394C2zhzgzM3-EHcO3ODMzc4c4NjbnCmBmdq8D7UYPHL4vLn1SLD84c37ww6IlA_-53RLErYu3fzxkvlOpSi0MdIoClC2r8k-piQv2Rc30E4z4V1LqzvLayIkAMPw84LsJYcfV7lUHqJ586B9dJoHOhBY9uXrB0MkfMW0QmiU4xYhliGOweOhn-0R5yEstPwT69W_0Asm5dWFhzR5YV0jjenEq9v1N_AeDoJ4xuj8d-4xjjBcYzYfDRtDziZJhT_vAqI4odG4wwKzBJMWfg7RWzOWpkEX9-ssHTChaewGG8rb8oSsYywdBj_F7YTxOatA3F8YvutfycyiI5evmx8HP8742sQXwk8HR2Mrxo4DfxVZvhuxk8jfzX-TZmfvoz6G7sovfxWGbVF9x_m6EcsDxInf1h1vIPt37M2xjH51ueIDHSPNvMDGcD909qT9DsMe-mx89w37gt7YJ_U_Obdw17D6W5pd7w1HrDfcR9iCrcoGsdYGHAa0dRjB1Bhb3AOGPY11wJEhFc76bB02Gg8TMokH45TTqeCFnwIbCRKlhaM83TKYz4p4mFeDMtoIGZMTNmUD2CWpHQ8SuNJOhnsZpO4KJOYCTphwyTOgRY8ZiUfTsaTySjO-UDODitLksRJkkY5Y-kwn7J8ksMU8gINY6i4VJFSj1Vk7HYgnWtglsST6SgdKJ6Dcu0uMqVHfZ5SNMoGdtbuqObN1qFhrKTz7lWPl161-89H00YZ_toqFFLbonIEZWlsxX2Xbv8iuOc4hJMPGqtmO-_rkHlEl4gut9LvmjwqTBXWTvV4OJHamn9CEVbQNrCwEPaxPc7ovwIAAP__YMDOgg">