MantisBT - CMake
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IDProjectCategoryView StatusDate SubmittedLast Update
0015953CMakeCMakepublic2016-02-04 03:142016-06-10 14:21
Reporterjbauer 
Assigned ToGregor Jasny 
PrioritynormalSeverityminorReproducibilityalways
StatusclosedResolutionfixed 
PlatformAppleOSOS XOS Version10.11.3
Product VersionCMake 3.4.3 
Target VersionCMake 3.6Fixed in VersionCMake 3.6 
Summary0015953: CMake Does Not Use -isystem with GCC on OS X
DescriptionOn OS X with the GCC compiler, CMake does not pass the -isystem flag to build commands for libraries configured with SYSTEM. For example, if target 'cmake_test' has an include added as 'target_include_directories( cmake_test SYSTEM PRIVATE ${PNG_INCLUDE_DIRS} )', -isystem will not be added on OS X with GCC.
Steps To ReproduceUse the 'target_include_directories' command with the SYSTEM option on OS X with GCC.

A minimal project that reproduces this issue has been provided via:
https://github.com/digitalriptide/cmake_test [^]
Additional Information
TagsNo tags attached.
Relationships
related to 0004462closed Brad King Do not use -isystem on Mac OS X 
related to 0010837closed Gregor Jasny GCC flag -isystem not applied on OS X 
Attached Files
Issue History
Date ModifiedUsernameFieldChange
2016-02-04 03:14jbauerNew Issue
2016-02-04 08:24Brad KingNote Added: 0040438
2016-02-04 08:41Gregor JasnyAssigned To => Gregor Jasny
2016-02-04 08:41Gregor JasnyStatusnew => assigned
2016-02-07 07:18Gregor JasnyRelationship addedrelated to 0004462
2016-02-07 07:47Gregor JasnyRelationship addedrelated to 0010837
2016-02-07 14:45Gregor JasnyNote Added: 0040442
2016-02-09 10:11Brad KingNote Added: 0040448
2016-02-09 10:11Brad KingStatusassigned => resolved
2016-02-09 10:11Brad KingResolutionopen => fixed
2016-02-09 10:11Brad KingFixed in Version => CMake 3.6
2016-02-09 10:11Brad KingTarget Version => CMake 3.6
2016-06-10 14:21Kitware RobotNote Added: 0041264
2016-06-10 14:21Kitware RobotStatusresolved => closed

Notes
(0040438)
Brad King   
2016-02-04 08:24   
This is due to a condition here:

 https://cmake.org/gitweb?p=cmake.git;a=blob;f=Modules/Compiler/GNU.cmake;hb=v3.4.3#l55 [^]

 if(NOT APPLE)
   set(CMAKE_INCLUDE_SYSTEM_FLAG_${lang} "-isystem ")
 endif()

which is present because at one time gcc on Apple did not support the flag. The condition may need to be updated to check the version/vendor of gcc.
(0040442)
Gregor Jasny   
2016-02-07 14:45   
I pushed apple-isystem-gcc topic containing
https://cmake.org/gitweb?p=stage/cmake.git;a=commit;h=2cae5128fdc6316a7f0913cb89ec467b33b9715b [^]

This will be available with CMake 3.6. In the meatime you could work around by adding something like this to your root CMakeLists.txt:
if(APPLE)
  set(CMAKE_INCLUDE_SYSTEM_FLAG_C "-isystem ")
  set(CMAKE_INCLUDE_SYSTEM_FLAG_CXX "-isystem ")
endif()
(0040448)
Brad King   
2016-02-09 10:11   
Re 0015953:0040442: Thanks. The commit is now in 'master':

 Apple: Enable -isystem for GNU Compiler >= 4
 https://cmake.org/gitweb?p=cmake.git;a=commitdiff;h=2cae5128 [^]
(0041264)
Kitware Robot   
2016-06-10 14:21   
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