check for timegm() function to avoid slow fallback implementation#705
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lauft merged 1 commit intoAug 27, 2025
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…ke.h This fix will cause cmake to detect and define HAVE_TIMEGM in cmake.h if the system libc has a timegm() function, and updates the libshared peg to incorporate cmake.h in the included libshared build. This way, the slow Datetime::timegm() implementation is not used, but rather the fast one in libc. This fast one depends on HAVE_TIMEGM being defined by the function in libshared's Datetime.cpp. Fixes GothenburgBitFactory#703 which was a significant performance regression in 1.9.0 release. Signed-off-by: Scott Mcdermott <scott@smemsh.net>
lauft
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Aug 27, 2025
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Libshared pulled in a fallback
timegm()implementation in GothenburgBitFactory/libshared#99 that's quite slow and caused an unintentional performance regression in timewarrior, as documented in #703.The fix is to have
cmaketest for systemtimegm()and set the proper define so the code won't build the fallback version, but rather use the system one.This patch brings in the libshared change from GothenburgBitFactory/libshared#105 that reads the cmake header, and then also adds the check+define in CMakeLists.txt so that the generated cmake.h that Datetime will now see (from libshared change) includes the right #define to avoid the slow fallback.
Fixes #703