[cmake-developers] [CMake 0015359]: __attribute__((weak)) support/detection (weak symbols)

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://public.kitware.com/Bug/view.php?id=15359 
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Reported By:                Laurent Demailly
Assigned To:                
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Project:                    CMake
Issue ID:                   15359
Category:                   CMake
Reproducibility:            always
Severity:                   feature
Priority:                   normal
Status:                     new
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Date Submitted:             2015-01-19 16:39 EST
Last Modified:              2015-01-19 16:39 EST
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Summary:                    __attribute__((weak)) support/detection (weak
symbols)
Description: 
it would be great if some built in recipe would set some variable depending on
whether the
compiler/linker support  __attribute__((weak))


this is done in autoconf the following way for instance:

AC_CACHE_CHECK(
  [for weak symbol support],
  [folly_cv_prog_cc_weak_symbols],
  [AC_LINK_IFELSE(
    [AC_LANG_SOURCE[
      extern "C" void configure_link_extern_weak_test()
__attribute__((weak));
      int main(int argc, char** argv) {
          return configure_link_extern_weak_test == nullptr;
      }]],
    [folly_cv_prog_cc_weak_symbols="yes"],
    [folly_cv_prog_cc_weak_symbols="no"])])

if test "$folly_cv_prog_cc_weak_symbols" = yes; then
  AC_DEFINE([HAVE_WEAK_SYMBOLS], [1],
            [Define to 1 if the linker supports weak symbols.])
fi


ps: sent similar request (more of a question on how to do it pending built in
support by cmake base) to the cmake at cmake.org mailing list - hope it's ok to
have some amount of duplicate

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Issue History 
Date Modified    Username       Field                    Change               
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2015-01-19 16:39 Laurent DemaillyNew Issue                                    
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