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| author | Stephen Sorley <ssorley@monetra.com> | 2017-01-12 18:10:25 (GMT) |
|---|---|---|
| committer | Brad King <brad.king@kitware.com> | 2017-01-12 20:52:53 (GMT) |
| commit | 4ae2dcb1b965efac7c088cbf97fa66c4d3c41858 (patch) | |
| tree | 701443bfe13ecee2433e3dc8f89e74a81ab67c4f /Modules/CheckFunctionExists.cmake | |
| parent | 728820f3ea0faf55ffe1236a44a35e9197fc6291 (diff) | |
| download | CMake-4ae2dcb1b965efac7c088cbf97fa66c4d3c41858.zip CMake-4ae2dcb1b965efac7c088cbf97fa66c4d3c41858.tar.gz CMake-4ae2dcb1b965efac7c088cbf97fa66c4d3c41858.tar.bz2 | |
CheckFunctionExists: Document suggestion to use CheckSymbolExists instead.
CheckFunctionExists has some severe limitations that are overcome by
CheckSymbolExists. Document them and suggest the alternative.
Diffstat (limited to 'Modules/CheckFunctionExists.cmake')
| -rw-r--r-- | Modules/CheckFunctionExists.cmake | 30 |
1 files changed, 21 insertions, 9 deletions
diff --git a/Modules/CheckFunctionExists.cmake b/Modules/CheckFunctionExists.cmake index 5f049e7..ef08062 100644 --- a/Modules/CheckFunctionExists.cmake +++ b/Modules/CheckFunctionExists.cmake @@ -5,18 +5,16 @@ # CheckFunctionExists # ------------------- # -# Check if a C function can be linked +# Check if a C function can be linked:: # -# CHECK_FUNCTION_EXISTS(<function> <variable>) +# check_function_exists(<function> <variable>) # -# Check that the <function> is provided by libraries on the system and -# store the result in a <variable>. This does not verify that any -# system header file declares the function, only that it can be found at -# link time (consider using CheckSymbolExists). -# <variable> will be created as an internal cache variable. +# Check that the ``<function>`` is provided by libraries on the system and store +# the result in a ``<variable>``. ``<variable>`` will be created as an internal +# cache variable. # -# The following variables may be set before calling this macro to modify -# the way the check is run: +# The following variables may be set before calling this macro to modify the +# way the check is run: # # :: # @@ -25,6 +23,20 @@ # CMAKE_REQUIRED_INCLUDES = list of include directories # CMAKE_REQUIRED_LIBRARIES = list of libraries to link # CMAKE_REQUIRED_QUIET = execute quietly without messages +# +# .. note:: +# +# Prefer using :Module:`CheckSymbolExists` instead of this module, +# for the following reasons: +# +# * ``check_function_exists()`` can't detect functions that are inlined +# in headers or specified as a macro. +# +# * ``check_function_exists()`` can't detect anything in the 32-bit +# versions of the Win32 API, because of a mismatch in calling conventions. +# +# * ``check_function_exists()`` only verifies linking, it does not verify +# that the function is declared in system headers. macro(CHECK_FUNCTION_EXISTS FUNCTION VARIABLE) if(NOT DEFINED "${VARIABLE}" OR "x${${VARIABLE}}" STREQUAL "x${VARIABLE}") |