MantisBT - CMake
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IDProjectCategoryView StatusDate SubmittedLast Update
0011565CMakeCMakepublic2010-12-02 16:352016-06-10 14:31
ReporterDaniel Richard G. 
Assigned ToKitware Robot 
PrioritynormalSeverityfeatureReproducibilityalways
StatusclosedResolutionmoved 
PlatformOSOS Version
Product VersionCMake-2-8 
Target VersionFixed in Version 
Summary0011565: CHECK_{FUNCTION,LIBRARY}_EXISTS() macros need a way to specify function declaration
DescriptionI want to check for the existence of a library+function. On Windows, however, the function must be declared using the WINAPI keyword (which is available after #including<windows.h>) in order for the linker to find it. This keyword changes the symbol that the linker looks for in a manner that cannot otherwise be represented in valid C code, so there is no alternative to its use.

There is currently no way to shoehorn this keyword into the C file used by the CHECK_{FUNCTION,LIBRARY}_EXISTS() macros, or otherwise to modify the trivial "char foo();" function declaration therein; the best you can do is create a custom C file and invoke TRY_COMPILE() yourself.
Steps To Reproduce
Additional Information
TagsNo tags attached.
Relationships
related to 0010090closed Brad King check_prototype_definition() - Check if the protoype we expect is correct 
Attached Files
Issue History
Date ModifiedUsernameFieldChange
2010-12-02 16:35Daniel Richard G.New Issue
2011-01-17 12:57David ColeNote Added: 0024777
2011-01-17 12:57David ColeAssigned To => David Cole
2011-01-17 12:57David ColeStatusnew => assigned
2011-01-17 13:17Daniel Richard G.Note Added: 0024781
2011-01-17 13:20Daniel Richard G.Note Edited: 0024781bug_revision_view_page.php?bugnote_id=24781#r135
2011-01-17 14:34David ColeRelationship addedrelated to 0010090
2011-02-09 13:58David ColeStatusassigned => backlog
2011-02-09 13:59David ColeAssigned ToDavid Cole =>
2011-03-18 14:11Brad KingNote Added: 0025820
2011-03-18 14:41Daniel Richard G.Note Added: 0025823
2016-06-10 14:28Kitware RobotNote Added: 0041767
2016-06-10 14:28Kitware RobotStatusbacklog => resolved
2016-06-10 14:28Kitware RobotResolutionopen => moved
2016-06-10 14:28Kitware RobotAssigned To => Kitware Robot
2016-06-10 14:31Kitware RobotStatusresolved => closed

Notes
(0024777)
David Cole   
2011-01-17 12:57   
I suggest invoking try_compile yourself with exactly the right details according to what you're looking for.

Do you have a suggestion for making this a more general purpose facility? A concrete proposed patch, including documentation and testing...?

Are you currently using a home-made CMake macro or function of any sort?
(0024781)
Daniel Richard G.   
2011-01-17 13:17   
(edited on: 2011-01-17 13:20)
I'm using try_compile() directly at the moment, but it seems silly to have to do that when all you want to change is a small part of the function declaration.

What about a new variable that can be set before calling the function to modify the declaration? Where you could do e.g.

    set(CMAKE_REQUIRED_DECLARATION "WINAPI int")

and that gets used in the C code instead of "char"?

Of course, that would also need the Windows header... maybe something like

    set(CMAKE_REQUIRED_PREAMBLE "#ifdef WIN32\n#include<windows.h>\n#endif")

as well?
(0025820)
Brad King   
2011-03-18 14:11   
Please see the fix to issue 0010090:

  http://cmake.org/gitweb?p=cmake.git;a=commitdiff;h=4f252abe [^]

Is this sufficient?
(0025823)
Daniel Richard G.   
2011-03-18 14:41   
In my particular case, I'm checking for a function in a library for which no header file is available. (I.e. the consuming code provides the prototype.)

A link stage is still necessary, especially here when it's with a non-default ABI.
(0041767)
Kitware Robot   
2016-06-10 14:28   
Resolving issue as `moved`.

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