llvm-project/lld
Fangrui Song 7bafaf8ffe Reland "Change the timestamp of llvmcache-foo file to meet the thinLTO prune policy"
Summary:
It is difficult to touch a file with a relative mtime across different OSes as POSIX touch -d is rigid. While we may construct relative timestamps with `date`, POSIX date is inadequate to do so as various OSes' date do not agree on a common format (OpenBSD uses `date -r seconds`, FreeBSD uses `date -v-2M` while GNU accepts `-d '-2 min'`)

Just use python os.utime()

Original description:

    The case may randomly fail if we test it with command "
     while llvm-lit tools/lld/test/ELF/lto/cache.ll; do true; done". It is because the llvmcache-foo file is younger than llvmcache-349F039B8EB076D412007D82778442BED3148C4E and llvmcache-A8107945C65C2B2BBEE8E61AA604C311D60D58D6. But due to timestamp precision reason their timestamp is the same. Given the same timestamp, the file prune policy is to remove bigger size file first, so mostly foo file is removed for its bigger size. And the files size is under threshold after deleting foo file. That's what test case expect.

    However sometimes, the precision is enough to measure that timestamp of llvmcache-349F039B8EB076D412007D82778442BED3148C4E and llvmcache-A8107945C65C2B2BBEE8E61AA604C311D60D58D6 are smaller than foo, so llvmcache-349F039B8EB076D412007D82778442BED3148C4E and llvmcache-A8107945C65C2B2BBEE8E61AA604C311D60D58D6 are deleted first. Since the files size is still above the file size threshold after deleting the 2 files, the foo file is also deleted. And then the test case fails, because it expect only one file should be deleted instead of 3.

    The fix is to change the timestamp of llvmcache-foo file to meet the thinLTO prune policy.
    The same fix is applied to llvm code at https://reviews.llvm.org/D52452.

    Patch by Luo Yuanke.

Reviewers: ruiu, craig.topper, smaslov, Jianping, espindola, LuoYuanke, tejohnson

Reviewed By: tejohnson

Subscribers: sbc100, krytarowski, aheejin, llvm-commits, dexonsmith, steven_wu, arichardson, inglorion, emaste, bjope, rupprecht

Differential Revision: https://reviews.llvm.org/D54039

llvm-svn: 346006
2018-11-02 17:44:30 +00:00
..
COFF Set MAttrs in LTO mode 2018-11-01 20:02:49 +00:00
Common Set MAttrs in LTO mode 2018-11-01 20:02:49 +00:00
ELF [ELF] Change sh_link of .rel{,a}.plt to make GNU strip happy 2018-11-01 22:28:58 +00:00
MinGW [MinGW] Pass libpath to the COFF linker 2018-10-10 09:00:03 +00:00
cmake/modules [CMake] Properly conditionalize installation of lld libraries 2018-03-09 13:09:36 +00:00
docs Add an entry to the release notes. 2018-10-09 17:53:33 +00:00
include/lld Set MAttrs in LTO mode 2018-11-01 20:02:49 +00:00
lib Fix clang -Wimplicit-fallthrough warnings across llvm, NFC 2018-11-01 19:54:45 +00:00
test Reland "Change the timestamp of llvmcache-foo file to meet the thinLTO prune policy" 2018-11-02 17:44:30 +00:00
tools/lld Fix typo in error message. NFC. 2018-09-13 15:37:13 +00:00
unittests [Darwin] Use errorHandler from liblldCommon 2018-06-12 02:34:04 +00:00
utils
wasm Set MAttrs in LTO mode 2018-11-01 20:02:49 +00:00
.arcconfig
.clang-format
.gitignore
CMakeLists.txt
CODE_OWNERS.TXT
LICENSE.TXT Update copyright year to 2018. 2018-06-18 12:22:17 +00:00
README.md

README.md

LLVM Linker (lld)

This directory and its subdirectories contain source code for the LLVM Linker, a modular cross platform linker which is built as part of the LLVM compiler infrastructure project.

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