gperftools 2.16 is out!
This release doesn't have major fixes or big headline features, but it has quite a lot of internal modernizations and cleanups. By the number of commits, 2.16 is going to be our biggest release ever.
This release's main focus was making our code and building infrastructure simpler, more straightforward, more portable, and more modern.
Please note that the gperftools 2.16 release will be the last release with the heap leak checker included. The time has come to drop this feature entirely. All users should migrate to relevant gcc/clang sanitizers.
Here are the most notable changes:
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we've upgraded our C++ standard to C++ 17. Some fraction of our code base was modernized.
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We've integrated (vendored copy of) GoogleTest, and most tests now use it. GoogleTest has helped us eliminate some legacy code and reduce the number of tests that use shell scripts.
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There are no more unnecessary wrappers around mutexes and threads for unit tests. We now use C++ standard mutexes and threads in our tests.
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We've done the bulk of the work necessary to enable hidden visibility. The most significant change is that tests no longer reach into libtcmalloc's guts. We use a special TestingPortal interface instead. We now offer the --enable-hidden-visibility configure option, which does what it says. But please note that hidden visibility is off by default for now.
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autotools build was significantly refactored, modernized and simplified.
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The cmake build has also been radically simplified. The previous version attempted to duplicate the same complexity that we had in the autotools build and did not do it very well. More tests now pass under cmake. But please note that cmake support is still not entirely functional, and we're not yet able to promise anything about it.
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Thread-local storage access and emergency malloc integration have been reworked. We now support emergency malloc even on systems with emutls and similarly "bad" TLS support. As a result, backtracing is now more reliable (e.g., on QNX).
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OSX operator new/delete performance has been improved. OSX's malloc performance is badly compromised by its support of malloc zones, so we cannot help much (the same applies to much of our competition among memory allocators). But the C++ new/delete API doesn't have to integrate with this stuff, so we now directly replace those functions for a sizeable speedup. Note that OSX performance is still not on par with other "prime tier" OSes due to its lack of efficient TLS support.
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Long deprecated google/ headers have been deleted (use, e.g., "gperftools/tcmalloc.h" instead)
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All clang builds now use -Wthread-safety and actually check thread-safety declarations
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Our code has stopped being incompatible with _TIME_BITS=64 on modern GNU Linux systems (relevant only for 32-bit systems)
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OpenSolaris build has been verified and fixed when needed
Thanks to the following people for code contributions:
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Github user oPiZiL (build fix for gcc 7.5)
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Github user zhangdexin (qnx fixes)
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Ishant Goyal (support for configuring minimal per-thread cache size)
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Lennox Ho (several build fixes and several fixes around Windows support)
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Olivier Langlois
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Sergey Fedorovhas (another fix for building gperftools on old PPC
OSX computers) -
Xiang.Lin (several OSX fixes)
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Yikai Zhao (aarch64 generic_fp stack frame validation)
You can find the list of all GitHub issues fixes in this release here:
https://github.com/gperftools/gperftools/issues?q=label%3Afixed-in-2.16+is%3Aclosed