6 Release date: 2018-09-02
11 - Fixed a race condition when creating the initial config file in the cache
14 - Bail out on too hard clang option `-MJ`.
16 - Bail out on too hard option `-save-temps=obj`.
18 - Handle separate parameter to clang option `-target` correctly.
20 - Upgraded bundled zlib to version 1.2.11.
25 Release date: 2018-03-25
30 - The cleanup algorithm has been fixed to not misbehave when files are removed
31 by another process while the cleanup process is running. Previously, too many
32 files could be removed from the cache if multiple cleanup processes were
33 triggered at the same time, in extreme cases trimming the cache to a much
34 smaller size than the configured limits.
36 - Correctly hash preprocessed headers located in a ``.gch directory''.
37 Previously, ccache would not pick up changes to such precompiled headers,
38 risking false positive cache hits.
40 - Fixed build failure when using the bundled zlib sources.
42 - ccache 3.3.5 added a workaround for not triggering Clang errors when a
43 precompiled header's dependency has an updated timestamp (but identical
44 content). That workaround is now only applied when the compiler is Clang.
46 - Made it possible to perform out-of-source builds in dev mode again.
51 Release date: 2018-02-11
56 - Fixed printing of version number in `ccache --version`.
61 Release date: 2018-02-11
63 New features and enhancements
64 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
66 - The compiler option form `--sysroot arg` is now handled like the documented
69 - Added support for caching `.su` files generated by GCC flag `-fstack-usage`.
71 - ccache should now work with distcc's ``pump'' wrapper.
73 - The optional unifier is no longer disabled when the direct mode is enabled.
75 - Added support for NVCC compiler options `--compiler-bindir/-ccbin`,
76 `--output-directory/-odir` and `--libdevice-directory/-ldir`.
78 - Boolean environment variable settings no longer accept the following
79 (case-insensitive) values: `0`, `false`, `disable` and `no`. All other values
80 are accepted and taken to mean ``true''. This is to stop users from setting
81 e.g. `CCACHE_DISABLE=0` and then expect the cache to be used.
83 - Improved support for `run_second_cpp = false`: If combined with passing
84 `-fdirectives-only` (GCC) or `frewrite-includes` (Clang) to the compiler,
85 diagnostics warnings and similar will be correct.
87 - An implicit `-MQ` is now passed to the preprocessor only if the object file
88 extension is non-standard. This should make it easier to use EDG-based
89 compilers (e.g. GHS) which don't understand `-MQ`.
91 - ccache now treats an unreadable configuration file just like a missing
94 - Documented more pitfalls with enabling `hard_links` (`CCACHE_HARDLINK`).
96 - Documented caveats related to colored warnings from compilers.
102 - File size and number counters are now updated correctly when files are
103 overwritten in the cache, e.g. when using `CCACHE_RECACHE`.
105 - `run_second_cpp` is now forced for NVCC.
107 - Fixed how the NVCC options `-optf` and `-odir` are handled.
112 Release date: 2018-01-28
114 New features and enhancements
115 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
117 - Improved instructions on how to get cache hits between different working
124 - Fixed regression in ccache 3.3.5 related to the `UNCACHED_ERR_FD` feature.
129 Release date: 2018-01-13
132 New features and enhancements
133 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
135 - Documented how automatic cache cleanup works.
141 - Fixed a regression where the original order of debug options could be lost.
142 This reverts the ``Improved parsing of `-g*` options'' feature in ccache 3.3.
144 - Multiple `-fdebug-prefix-map` options should now be handled correctly.
146 - Fixed matching of directories in the `ignore_headers_in_manifest`
147 configuration option.
149 - Fixed detection of missing argument to `-opt`/`--options-file`.
151 - ccache now bails out when building a precompiled header if any of the
152 corresponding header files has an updated timestamp. This fixes complaints
155 - Fixed a bug related to erroneously storing a dependency file with absolute
156 paths in the cache on a preprocessed hit.
158 - `ccache -c/--cleanup` now works like documented: it just recalculates size
159 counters and trims the cache to not exceed the max size and file number
160 limits. Previously, the forced cleanup took ``limit_multiple'' into account,
161 so that `ccache -c/--cleanup` by default would trim the cache to 80% of the
164 - ccache no longer ignores linker arguments for Clang since Clang warns about
167 - Plugged a couple of file descriptor leaks.
169 - Fixed a bug where ccache would skip hashing the compiler argument following a
170 `-fno-working-directory`, `-fworking-directory`, `-nostdinc`, `-nostdinc++`,
171 `-remap` or `-trigraphs` option in preprocessor mode.
176 Release date: 2017-02-17
178 New features and enhancements
179 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
181 - Documented the different cache statistics counters.
187 - Fixed a regression in ccache 3.3 related to potentially bad content of
188 dependency files when compiling identical source code but with different
189 source paths. This was only partially fixed in 3.3.2 and reverts the new
190 ``Names of included files are no longer included in the hash of the
191 compiler's preprocessed output'' feature in 3.3.
193 - Corrected statistics counter for `-optf`/`--options-file` failure.
195 - Fixed undefined behavior warnings in ccache found by `-fsanitize=undefined`.
199 Release date: 2016-10-26
204 - ccache now detects usage of `.incbin` assembler directives in the source code
205 and avoids caching such compilations.
210 Release date: 2016-09-28
215 - Fixed a regression in ccache 3.3 related to potentially bad content of
216 dependency files when compiling identical source code but with different
219 - Fixed a regression in ccache 3.3.1: ccache could get confused when using the
220 compiler option `-Wp,` to pass multiple options to the preprocessor,
221 resulting in missing dependency files from direct mode cache hits.
226 Release date: 2016-09-07
231 - Fixed a problem in the ``multiple `-arch` options'' support introduced in
232 3.3. When using the direct mode (the default), different combinations of
233 `-arch` options were not detected properly.
235 - Fixed an issue when compiler option `-Wp,-MT,path` is used instead of `-MT
236 path` (and similar for `-MF`, `-MP` and `-MQ`) and `run_second_cpp`
237 (`CCACHE_CPP2`) is enabled.
242 Release date: 2016-08-27
247 - A C99-compatible compiler is now required to build ccache.
250 New features and enhancements
251 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
253 - The configuration option `run_second_cpp` (`CCACHE_CPP2`) now defaults to
254 true. This improves ccache's out-of-the-box experience for compilers that
255 can't compile their own preprocessed output with the same outcome as if they
256 compiled the real source code directly, e.g. newer versions of GCC and Clang.
258 - The configuration option `hash_dir` (`CCACHE_HASHDIR`) now defaults to true.
260 - Added a new `ignore_headers_in_manifest` configuration option, which
261 specifies headers that should be ignored in the direct mode.
263 - Added a new `prefix_command_cpp` (`CCACHE_PREFIX_CPP`) configuration option,
264 which specifies one or several prefixes to add to the command line ccache
265 uses when invoking the preprocessor.
267 - Added a new `limit_multiple` (`CCACHE_LIMIT_MULTIPLE`) configuration option,
268 which specifies how much of the cache to remove when cleaning.
270 - Added a new `keep_comments_cpp` (`CCACHE_COMMENTS`) configuration option,
271 which tells ccache not to discard the comments before hashing preprocessor
272 output. This can be used to check documentation with *-Wdocumentation*.
274 - Added a new sloppiness option `no_system_headers`, which tells ccache not to
275 include system headers in manifest files.
277 - Added a new statistics counter that tracks the number of performed cleanups
278 due to the cache size being over the limit. The value is shown in the output
281 - Added support for relocating debug info directory using `-fdebug-prefix-map`.
282 This allows for cache hits even when `hash_dir` is used in combination with
285 - Added a new ``cache hit rate'' field to the output of ``ccache -s''.
287 - Added support for caching compilation of assembler code produced by e.g.
290 - Added support for cuda including the -optf/--options-file option.
292 - Added support for Fortran 77.
294 - Added support for multiple `-arch` options to produce "fat binaries".
296 - Multiple identical `-arch` arguments are now handled without bailing.
298 - The concatenated form of some long compiler options is now recognized, for
299 example when using `-isystemPATH` instead of `-isystem PATH`.
301 - If hard-linking is enabled and but fails (e.g. due to cross-device linking),
302 ccache now falls back to copying instead of running the compiler.
304 - Made the `hash_dir` option only have effect when generating debug info.
306 - ccache now knows how to convert absolute paths to relative paths inside
307 dependency files when using `base_dir`.
309 - Improved parsing of `-g*` options.
311 - Made ccache understand `-Wp,-D*` options.
313 - ccache now understands the undocumented `-coverage` (only one dash) GCC
316 - Names of included files are no longer included in the hash of the compiler's
317 preprocessed output. This leads to more potential cache hits when not using
320 - Increased buffer size used when reading file data. This improves performance
327 - Bail out on too hard compiler option `-P`.
329 - Fixed Clang test suite when running on Linux.
331 - Fixed build and test for MinGW32 and Windows.
336 Release date: 2016-09-28
341 - Fixed a regression in ccache 3.2.8: ccache could get confused when using the
342 compiler option `-Wp,` to pass multiple options to the preprocessor,
343 resulting in missing dependency files from direct mode cache hits.
348 Release date: 2016-09-07
353 - Fixed an issue when compiler option `-Wp,-MT,path` is used instead of `-MT
354 path` (and similar for `-MF`, `-MP` and `-MQ`) and `run_second_cpp`
355 (`CCACHE_CPP2`) is enabled.
357 - ccache now understands the undocumented `-coverage` (only one dash) GCC
363 Release date: 2016-07-20
368 - Fixed a bug which could lead to false cache hits for compiler command lines
369 with a missing argument to an option that takes an argument.
371 - ccache now knows how to work around a glitch in the output of GCC 6's
377 Release date: 2016-07-12
382 - Fixed build problem on QNX, which lacks ``SA_RESTART''.
384 - Bail out on compiler option `-fstack-usage` since it creates a `.su` file
385 which ccache currently doesn't handle.
387 - Fixed a bug where (due to ccache rewriting paths) the compiler could choose
388 incorrect include files if `CCACHE_BASEDIR` is used and the source file path
389 is absolute and is a symlink.
394 Release date: 2016-04-17
397 New features and enhancements
398 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
400 - Only pass Clang-specific `-stdlib=` to the preprocessor.
402 - Improved handling of stale NFS handles.
404 - Made it harder to misinterpret documentation of boolean environment settings'
411 - Include m4 files used by configure.ac in the source dist archives.
413 - Corrected "Performance" section in the manual regarding `__DATE_`, `__TIME__`
414 and `__FILE__` macros.
416 - Fixed build on Solaris 10+ and AIX 7.
418 - Fixed failure to create directories on QNX.
420 - Don't (try to) update manifest file in ``read-only'' and ``read-only direct''
423 - Fixed a bug in caching of `stat` system calls in ``file_stat_matches
426 - Fixed bug in hashing of Clang plugins, leading to unnecessary cache misses.
428 - Fixed --print-config to show ``pch_defines sloppiness''.
430 - The man page is now built when running ``make install'' from Git repository
436 Release date: 2015-10-08
442 - Fixed build error related to zlib on systems with older make versions
443 (regression in ccache 3.2.3).
445 - Made conversion-to-bool explicit to avoid build warnings (and potential
446 runtime errors) on legacy systems.
448 - Improved signal handling: Kill compiler on SIGTERM; wait for compiler to exit
449 before exiting; die appropriately.
451 - Minor fixes related to Windows support.
453 - The correct compression level is now used if compression is requested.
455 - Fixed a bug where cache cleanup could be run too early for caches larger than
456 64 GiB on 32-bit systems.
461 Release date: 2015-08-16
464 New features and enhancements
465 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
467 - Added support for compiler option `-gsplit-dwarf`.
473 - Support external zlib in nonstandard directory.
475 - Avoid calling `exit()` inside an exit handler.
477 - Let exit handler terminate properly.
479 - Bail out on compiler option `--save-temps` in addition to `-save-temps`.
481 - Only log "Disabling direct mode" once when failing to read potential include
487 Release date: 2015-05-10
490 New features and enhancements
491 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
493 - Added support for `CCACHE_COMPILERCHECK=string:<value>`. This is a faster
494 alternative to `CCACHE_COMPILERCHECK=<command>` if the command's output can
495 be precalculated by the build system.
497 - Add support for caching code coverage results (compiling for gcov).
503 - Made hash of cached result created with and without `CCACHE_CPP2` different.
504 This makes it possible to rebuild with `CCACHE_CPP2` set without having to
505 clear the cache to get new results.
507 - Don't try to reset a non-existing stats file. This avoids ``No such file or
508 directory'' messages in the ccache log when the cache directory doesn't
511 - Fixed a bug where ccache deleted Clang diagnostics after compiler failures.
513 - Avoid performing an unnecessary copy of the object file on a cache miss.
515 - Bail out on too hard compiler option `-fmodules`.
517 - Bail out on too hard compiler option `-fplugin=libcc1plugin` (interaction
520 - Fixed build error when compiling ccache with recent Clang versions.
522 - Removed signal-unsafe code from signal handler.
524 - Corrected logic for when to output cached stderr.
526 - Wipe the whole cached result on failure retrieving a cached file.
528 - Fixed build error when compiling ccache with recent Clang versions.
533 Release date: 2014-12-10
539 - Fixed regression in temporary file handling, which lead to incorrect
540 permissions for stats, manifest and ccache.conf files in the cache.
542 - `CACHEDIR.TAG` files are now created in the [0-9a-f] subdirectories so that
543 ccache.conf is not lost in backups.
545 - Made the default cache size suffix `G`, as previously documented.
547 - `-fdiagnostics-color=auto` is now passed to the compiler even if stderr is
548 redirected. This fixes a problem when, for instance, a configure test probes
549 if the compiler (wrapped via ccache) supports `-fdiagnostics-color=auto`.
551 - Added missing documentation for `max_files` and `max_size` configuration
557 Release date: 2014-11-17
560 New features and enhancements
561 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
563 - Added support for configuring ccache via one or several configuration files
564 instead of via environment variables. Environment variables still have
565 priority but are no longer the recommended way of customizing ccache
566 behavior. See the manual for more information.
568 - Added support for compiler error/warning messages with color.
570 - Made creation of temporary directories and cache directories smarter to avoid
571 unnecessary `stat` calls.
573 - Improved efficiency of the algorithm that scans for `__DATE_` and `__TIME__`
574 tokens in the hashed source code.
576 - Added support for several binaries (separated by space) in `CCACHE_PREFIX`.
578 - The `-c` option is no longer passed to the preprocessor. This fixes problems
579 with Clang and Solaris's C++ compiler.
581 - ccache no longer passes preprocessor options like `-D` and `-I` to the
582 compiler when compiling preprocessed output. This fixes warnings emitted by
585 - Compiler options `-fprofile-generate`, `-fprofile-arcs`, `-fprofile-use` and
586 `-fbranch-probabilities` are now handled without bailing.
588 - Added support for Clang's `--serialize-diagnostic` option, storing the
589 diagnostic file (`.dia`) in the cache.
591 - Added support for precompiled headers when using Clang.
593 - Added support for Clang `.pth` (pretokenized header) files.
595 - Changed the `-x` language option to use the new objective C standard for GCC
598 - On a cache miss, ccache now instructs the compiler to create the object file
599 at the real destination and then copies the file into the cache instead of
600 the other way around. This is needed to support compiler options like
601 `-fprofile-arcs` and `--serialize-diagnostics`.
603 - ccache now checks that included files' ctimes aren't too new. This check can
604 be turned off by adding `include_file_ctime` to the ``ccache sloppiness''
607 - Added possibility to get cache hits based on filename, size, mtime and ctime
608 only. On other words, source code files are not even read, only stat-ed. This
609 operation mode is opt-in by adding `file_stat_matches` to the ``ccache
610 sloppiness'' setting.
612 - The filename part of options like `-Wp,-MDfilename` is no longer included in
613 the hash since the filename doesn't have any bearing on the result.
615 - Added a ``read-only direct'' configuration setting, which is like the
616 ordinary read-only setting except that ccache will only try to retrieve
617 results from the cache using the direct mode, not the preprocessor mode.
619 - The display and interpretation of cache size has been changed to use SI
622 - Default cache size is now 5 GB (was previously 1 GiB).
624 - Added configuration option to set the compression level of compressed object
627 - Added support for `@file` and `-@file` arguments (reading options from a
630 - `-Wl,` options are no longer included in the hash since they don't affect
633 - Bail out on too hard compiler option `-Wp,-P`.
635 - Optimized MD4 calculation code on little-endian systems.
637 - Various improvements and fixes on win32.
639 - Improved logging to the ccache log file.
641 - Added `--dump-manifest` command-line option for debugging purposes.
643 - Added `--with-bundled-zlib` configure option.
645 - Upgraded bundled zlib to version 1.2.8.
647 - Improved `dev.mk` to be more platform independent.
649 - Made the test suite work with Clang and gcc-llvm on OS X.
651 - Various other improvements of the test suite.
657 - Any previous `.stderr` is now removed from the cache when recaching.
659 - Fixed an issue when handling the `-arch` compiler option with an argument.
661 - Fixed race condition when creating the initial cache directory.
663 - Fixed test suite failures when `CC` is a ccache-wrapped compiler.
668 Release date: 2016-07-12
674 - Fixed a bug where (due to ccache rewriting paths) the compiler could choose
675 incorrect include files if `CCACHE_BASEDIR` is used and the source file path
676 is absolute and is a symlink.
681 Release date: 2015-03-07
687 - Fixed bug which could result in false cache hits when source code contains
688 `'"'` followed by `" /*"` or `" //"` (with variations).
690 - Made hash of cached result created with and without `CCACHE_CPP2` different.
691 This makes it possible to rebuild with `CCACHE_CPP2` set without having to
692 clear the cache to get new results.
694 - Don't try to reset a non-existing stats file. This avoids ``No such file or
695 directory'' messages in the ccache log when the cache directory doesn't
701 Release date: 2014-10-19
704 New features and enhancements
705 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
707 - Added support for the `-Xclang` compiler option.
709 - Improved handling of exit code of internally executed processes.
711 - Zero length object files in the cache are now rejected as invalid.
713 - Bail out on option `-gsplit-dwarf` (since it produces multiple output files).
715 - Compiler option `-fdebug-prefix-map` is now ignored (not part of the hash).
716 (The `-fdebug-prefix-map` option may be used in combination with
717 `CCACHE_BASEDIR` to reuse results across different directories.)
719 - Added note in documentation that `--ccache-skip` currently does not mean
720 ``don't hash the following option''.
722 - To enable support for precompiled headers (PCH), `CCACHE_SLOPPINESS` now also
723 needs to include the new `pch_defines` sloppiness. This is because ccache
724 can't detect changes in the source code when only defined macros have been
727 - Stale files in the internal temporary directory (`<ccache_dir>/tmp`) are now
728 cleaned up if they are older than one hour.
734 - Fixed path canonicalization in `make_relative_path()` when path doesn't
737 - Fixed bug in `common_dir_prefix_length()`. This corrects the `CCACHE_BASEDIR`
740 - ccache no longer tries to create the cache directory when `CCACHE_DISABLE` is
743 - Fixed bug when reading manifests with a very large number of file info
746 - Fixed problem with logging of current working directory.
751 Release date: 2013-01-06
757 - The EAGAIN signal is now handled correctly when emitting cached stderr
758 output. This fixes a problem triggered by large error outputs from the
761 - Subdirectories in the cache are no longer created in read-only mode.
763 - Fixed so that ccache's log file descriptor is not made available to the
766 - Improved error reporting when failing to create temporary stdout/stderr files
767 when executing the compiler.
769 - Disappearing temporary stdout/stderr files are now handled gracefully.
775 - Fixed test suite to work on ecryptfs.
780 Release date: 2012-08-11
783 New features and enhancements
784 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
786 - Made paths to dependency files relative in order to increase cache hits.
788 - Added work-around to make ccache work with buggy GCC 4.1 when creating a
791 - Clang plugins are now hashed to catch plugin upgrades.
797 - Fixed crash when the current working directory has been removed.
799 - Fixed crash when stderr is closed.
801 - Corrected a corner case when parsing backslash escapes in string
804 - Paths are now correctly canonicalized when computing paths relative to the
811 - Made git version macro work when compiling outside of the source directory.
813 - Fixed `static_assert` macro definition clash with GCC 4.7.
818 Release date: 2012-01-08
824 - Non-writable `CCACHE_DIR` is now handled gracefully when `CCACHE_READONLY` is
827 - Made failure to create files (typically due to bad directory permissions) in
828 the cache directory fatal. Previously, such failures were silently and
829 erroneously flagged as "compiler produced stdout".
831 - Both the `-specs=file` and `--specs=file` forms are now recognized.
833 - Added recognition and hashing of GCC plugins specified with `-fplugin=file`.
835 - `CCACHE_COMPILERCHECK` now also determines how to hash explicit specs files
838 - Added `CPATH`, `C_INCLUDE_PATH` and similar environment variables to the hash
839 to avoid false cache hits when such variables have changed.
841 - Corrected log message when unify mode is enabled.
843 - Reverted the GCC bug compatibility introduced in ccache 3.1.5 for `-MT`/`-MQ`
844 options with concatenated arguments. (The bug is fixed in recent GCC
851 - Corrected license header for `mdfour.c`.
853 - Improved documentation on how to fix bad object files in the cache.
859 Release date: 2011-08-21
862 New features and enhancements
863 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
865 - Rewrite argument to `--sysroot` if `CCACHE_BASEDIR` is used.
871 - Don't crash if `getcwd()` fails.
873 - Fixed alignment of ``called for preprocessing'' counter.
878 Release date: 2011-05-29
881 New features and enhancements
882 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
884 - Added a new statistics counter named ``called for preprocessing''.
886 - The original command line is now logged to the file specified with
889 - Improved error logging when system calls fail.
891 - Added support for rewriting absolute paths in `-F`/`-iframework` GCC
894 - Improved order of statistics counters in `ccache -s` output.
900 - The `-MF`/`-MT`/`-MQ` options with concatenated argument are now handled
901 correctly when they are last on the command line.
903 - ccache is now bug compatible with GCC for the `-MT`/`-MQ` options with
904 concatenated arguments.
906 - Fixed a minor memory leak.
908 - Systems that lack (and don't need to be linked with) libm are now supported.
913 Release date: 2011-01-09
919 - Made a work-around for a bug in `gzputc()` in zlib 1.2.5.
921 - Corrupt manifest files are now removed so that they won't block direct mode
924 - ccache now copes with file systems that don't know about symbolic links.
926 - The file handle in now correctly closed on write error when trying to create
932 Release date: 2010-11-28
938 - The -MFarg, -MTarg and -MQarg compiler options (i.e, without space between
939 option and argument) are now handled correctly.
945 - Portability fixes for HP-UX 11.00 and other esoteric systems.
950 Release date: 2010-11-21
956 - Bail out on too hard compiler options `-fdump-*`.
958 - NULL return values from malloc/calloc of zero bytes are now handled
961 - Fixed issue when parsing precompiler output on AIX.
967 - Improved documentation on which information is included in the hash sum.
969 - Made the ``too new header file'' test case work on file systems with
970 unsynchronized clocks.
972 - The test suite now also works on systems that lack a /dev/zero.
977 Release date: 2010-11-07
983 - ccache now falls back to preprocessor mode when a non-regular include file
984 (device, socket, etc) has been detected so that potential hanging due to
985 blocking reads is avoided.
987 - CRC errors are now detected when decompressing compressed files in the cache.
989 - Fixed potential object file corruption race on NFS.
991 - Minor documentation corrections.
993 - Fixed configure detection of ar.
995 - ccache development version (set by dev.mk) now works with gits whose
996 `describe` command doesn't understand `--dirty`.
1002 - Minor debug log message improvements.
1007 Release date: 2010-09-16
1010 New features and enhancements
1011 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1013 - Added support for hashing the output of a custom command (e.g. `%compiler%
1014 --version`) to identify the compiler instead of stat-ing or hashing the
1015 compiler binary. This can improve robustness when the compiler (as seen by
1016 ccache) actually isn't the real compiler but another compiler wrapper.
1018 - Added support for caching compilations that use precompiled headers. (See the
1019 manual for important instructions regarding this.)
1021 - Locking of the files containing statistics counters is now done using
1022 symlinks instead of POSIX locks. This should make ccache behave a lot better
1023 on file systems where POSIX locks are slow or broken (e.g. NFS on some
1026 - Manifest files are now updated without the need of taking locks.
1028 - Updates of statistics counters are now always done in one of the sub-level
1029 statistics files. This reduces lock contention, which especially improves
1030 performance on slow NFS mounts.
1032 - Reading and writing of statistics counters has been made forward-compatible
1033 (unknown counters are retained).
1035 - Files are now read without using `mmap()`. This has two benefits: it's more
1036 robust against file changes during reading and it improves performance on
1037 poor systems where `mmap()` doesn't use the disk cache.
1039 - Added `.cp` and `.CP` as known C++ suffixes.
1043 - Added `-install_name` as an option known to take an argument. (This improves
1044 statistics when using the Darwin linker.)
1050 - Non-fatal error messages are now never printed to stderr but logged instead.
1052 - Fixed a bug affecting failing commands when `--ccache-skip` is used.
1054 - Made `--ccache-skip` work for all options.
1056 - EINTR is now handled correctly.
1062 - Work on porting ccache to win32 (native), mostly done by Ramiro Polla. The
1063 port is not yet finished, but will hopefully be complete in some subsequent
1066 - Added a `--nostats` flag to the performance benchmark program.
1068 - Made the performance benchmark program more accurate when measuring cache
1071 - Added a new test framework for unit tests written in C.
1073 - Got rid of `configure-dev`; dev mode is now given by `dev.mk.in` presence.
1075 - Improved documentation on how to combine ccache with other compiler wrappers
1078 - New `LICENSE.txt` file with licensing and copyright details about bundled
1081 - New `AUTHORS.txt` file with a list of ccache contributors.
1083 - New `HACKING.txt` file with some notes about ccache code conventions.
1088 Release date: 2010-07-15
1094 - The statistics counter ``called for link'' is now correctly updated when
1095 linking with a single object file.
1097 - Fixed a problem with out-of-source builds.
1102 Release date: 2010-06-20
1108 - ccache is now licensed under the GNU General Public License (GPL) version 3
1115 - The way the hashes are calculated has changed, so you won't get cache hits
1116 for compilation results stored by older ccache versions. Because of this, you
1117 might as well clear the old cache directory with `ccache --clear` if you
1118 want, unless you plan to keep using an older ccache version.
1121 New features and enhancements
1122 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1124 - ccache now has a ``direct mode'' where it computes a hash of the source code
1125 (including all included files) and compiler options without running the
1126 preprocessor. By not running the preprocessor, CPU usage is reduced; the
1127 speed is somewhere between 1 and 5 times that of ccache running in
1128 traditional mode, depending on the circumstances. The speedup will be higher
1129 when I/O is fast (e.g., when files are in the disk cache). The direct mode
1130 can be disabled by setting +CCACHE_NODIRECT+.
1132 - Support has been added for rewriting absolute paths to relative paths when
1133 hashing, in order to increase cache hit rate when building the same source
1134 code in different directories even when compiling with `-g` and when using
1135 absolute include directory paths. This is done by setting the
1136 `CCACHE_BASEDIR` environment variable to an absolute path that specifies
1137 which paths to rewrite.
1139 - Object files are now optionally stored compressed in the cache. The runtime
1140 cost is negligible, and more files will fit in the ccache directory and in
1141 the disk cache. Set `CCACHE_COMPRESS` to enable object file compression. Note
1142 that you can't use compression in combination with the hard link feature.
1144 - A `CCACHE_COMPILERCHECK` option has been added. This option tells ccache what
1145 compiler-identifying information to hash to ensure that results retrieved
1146 from the cache are accurate. Possible values are: none (don't hash anything),
1147 mtime (hash the compiler's mtime and size) and content (hash the content of
1148 the compiler binary). The default is mtime.
1150 - It is now possible to specify extra files whose contents should be included
1151 in the hash sum by setting the `CCACHE_EXTRAFILES` option.
1153 - Added support for Objective-C and Objective-C\+\+. The statistics counter
1154 ``not a C/C++ file'' has been renamed to ``unsupported source language''.
1156 - Added support for the `-x` compiler option.
1158 - Added support for long command-line options.
1160 - A `CACHEDIR.TAG` file is now created in the cache directory. See
1161 <http://www.brynosaurus.com/cachedir/>.
1163 - Messages printed to the debug log (specified by `CCACHE_LOGFILE`) have been
1166 - You can relax some checks that ccache does in direct mode by setting
1167 `CCACHE_SLOPPINESS`. See the manual for more information.
1169 - `CCACHE_TEMPDIR` no longer needs to be on the same filesystem as
1172 - The default value of `CCACHE_TEMPDIR` has been changed to `$CCACHE_DIR/tmp`
1173 to avoid cluttering the top directory.
1175 - Temporary files that later will be moved into the cache are now created in
1176 the cache directory they will end up in. This makes ccache more friendly to
1177 Linux's directory layout.
1179 - Improved the test suite and added tests for most of the new functionality.
1180 It's now also possible to specify a subset of tests to run.
1182 - Standard error output from the compiler is now only stored in the cache if
1185 - If the compiler produces no object file or an empty object file, but gives a
1186 zero exit status (could be due to a file system problem, a buggy program
1187 specified by `CCACHE_PREFIX`, etc.), ccache copes with it properly.
1189 - Added `installcheck` and `distcheck` make targets.
1191 - Clarified cache size limit options' and cleanup semantics.
1193 - Improved display of cache max size values.
1195 - The following options are no longer hashed in the preprocessor mode:
1196 `-imacros`, `-imultilib`, `-iprefix`, `-iquote`, `-isysroot`, `-iwithprefix`,
1197 `-iwithprefixbefore`, `-nostdinc`, `-nostdinc++` and `-U`.
1203 - Various portability improvements.
1205 - Improved detection of home directory.
1207 - User-defined `CPPFLAGS` and `LDFLAGS` are now respected in the Makefile.
1211 - Computation of the hash sum has been improved to decrease the risk of hash
1212 collisions. For instance, the compiler options `-X -Y` and `-X-Y` previously
1213 contributed equally to the hash sum.
1215 - Bail out on too hard compiler options `--coverage`, `-fprofile-arcs`,
1216 `-fprofile-generate`, `-fprofile-use`, `-frepo`, `-ftest-coverage` and
1217 `-save-temps`. Also bail out on `@file` style options.
1219 - Errors when using multiple `-arch` compiler options are now noted as
1220 ``unsupported compiler option''.
1222 - `-MD`/`-MMD` options without `-MT`/`-MF` are now handled correctly.
1224 - The `-finput-charset` option is now handled correctly.
1226 - Added support for `-Wp,-MD` and `-Wp,-MMD` options.
1228 - The compiler options `-Xassembler`, `-b`, `-G` and `-V` are now correctly
1229 recognized as taking an argument.
1231 - Debug information containing line numbers of predefined and command-line
1232 macros (enabled with the compiler option `-g3`) will now be correct.
1234 - Corrected LRU cleanup handling of object files.
1236 - `utimes()` is now used instead of `utime()` when available.
1238 - Non-writable cache directories are now handled gracefully.
1240 - Corrected documentation about sharing the cache directory.
1242 - Fixed compilation warnings from GCC 4.3.
1244 - The command specified by `CCACHE_PREFIX` is no longer part of the hash.
1246 - Fixed bad memory access spotted by Valgrind.
1248 - Fixed a bug in `x_realloc`.
1250 - Freed memory is no longer referenced when compiling a `.i`/`.ii` file and
1251 falling back to running the real compiler.
1253 - The test suite is now immune to external values of the `CCACHE_*` environment
1256 - Improved detection of recursive invocation.
1258 - The ccache binary is now not unconditionally stripped when installing.
1260 - Statistics counters are now correctly updated for -E option failures and
projects / platform / upstream / ccache.git / blob