version 0.009; 2023-04-10

  * port to Perl 5.33.1, which defines a PERL_VERSION_GE() macro that
    clashes with the one this module previously had

  * skip thread tests on some old versions of Perl (around 5.10.0) where
    a core bug makes thread creation violate an internal assertion and
    causes crashes

  * skip thread tests on pre-5.8.9 Perls where a core bug makes thread
    creation corrupt memory

  * skip thread tests on pre-5.8.3 Perls where a core bug makes thread
    completion break the global PL_sv_placeholder

  * put whitespace around C string literals being pasted, for C++11
    compatibility

  * avoid using C preprocessor directives inside a macro argument list
    (which is not valid)

  * in XS code in the test suite, when croaking, avoid using __FILE__
    as part of a format string, in case it includes a metacharacter

  * document the intended scope of this module's backporting effort

  * fix a documentation wording glitch

  * in XS declare as const some data that never changes

  * refactor thread tests

  * in XS, refactor Perl version comparisons

  * in XS, rename some macros for better style

  * in XS, better argument parenthesisation in some macros

  * avoid some compiler warnings

  * in .gitignore, list temporary files produced by test XS compilation

version 0.008; 2017-07-26

  * update test suite to not rely on . in @INC, which is no longer
    necessarily there from Perl 5.25.7

  * no longer include a Makefile.PL in the distribution

  * in documentation, use four-column indentation for all verbatim
    material

  * in META.{yml,json}, point to public bug tracker

  * update op-munging code to the PERL_OP_PARENT-compatible style
    (though none of it is actually used on Perls new enough to support
    PERL_OP_PARENT)

  * in tests, revise PERL_OP_PARENT reserve definitions to simpler form,
    accommodating only Perl 5.21.11 or later

  * consistently use THX_ prefix on internal function names

version 0.007; 2015-03-21

  * update tests for PERL_OP_PARENT builds of Perl 5.21.2 or later

version 0.006; 2013-09-21

  * bugfix: allow generated headers to work on API-compatible Perls
    other than the specific version under which this module was installed

  * fix test for thread safety, which risked false negatives

  * avoid a C compiler warning in a test

version 0.005; 2012-02-11

  * be thread-safe, by idempotence and mutex control on op check hooking

  * load DynaLoader::Functions lazily, because it is only required at
    build time of users of this module, not required at all in normal
    runtime

  * avoid potential circular dependency chain, by requiring a version
    of DynaLoader::Functions that has reduced its dependencies

  * fix some C preprocessor directive indentation

version 0.004; 2012-02-01

  * in documentation, clarify that the header and linkable functions
    should be called at build time

  * add B::CallChecker to "see also" list

  * update tests to accept Perl 5.15.7's modified panic error messages

  * in Build.PL, declare incompatibility with pre-0.19
    B::Hooks::OP::Check, which doesn't play nicely around op check hooking

  * convert .cvsignore to .gitignore

version 0.003; 2011-05-29

  * bugfix: set up CV name links correctly for error messages from
    prototype checkers

  * bugfix: don't leak temporary GVs and CVs in prototype checkers

version 0.002; 2011-05-19

  * add callchecker_linkable constant to help users link with this module

  * fully document the C functions

  * avoid false test failures with parallel testing

  * correct abstract line

  * add Devel::CallParser to "see also" list

version 0.001; 2011-04-11

  * bugfix: use PERL_CALLCONV to achieve consistent ABI across compilers

  * port to Windows (GCC toolchain) and Cygwin, where additional linker
    magic is required to make importation from shared object work (MSVC
    and BCC on Windows presumably still don't generate the linkable
    version of the shared library)

version 0.000; 2011-04-03

  * initial released version