[cmake-developers] [CMake 0014572]: Xcode 4.6 gcc problems on Mac OS X 10.9

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://cmake.org/Bug/view.php?id=14572 
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Reported By:                Clinton Stimpson
Assigned To:                
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Project:                    CMake
Issue ID:                   14572
Category:                   CMake
Reproducibility:            have not tried
Severity:                   minor
Priority:                   normal
Status:                     new
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Date Submitted:             2013-11-16 18:24 EST
Last Modified:              2013-11-16 18:24 EST
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Summary:                    Xcode 4.6 gcc problems on Mac OS X 10.9
Description: 
CMake doesn't work well when trying to use gcc from Xcode 4.6 on Mac OS X 10.9.

I've installed Xcode 4.6 from the developer website.
Then did xcode-select /Applications/Xcode-4.6.app

Running
cmake -G Xcode 
gives
CMake Warning at .../Modules/Platform/Darwin.cmake:179 (message):
  Ignoring CMAKE_OSX_SYSROOT value:
  
/Applications/Xcode-4.6.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk
  because the directory does not exist.


But, if I want to use the gcc compiler instead, by running:
cmake -G Xcode -T com.apple.compilers.llvmgcc42 
it gives:
-- The C compiler identification is unknown
-- The CXX compiler identification is unknown
-- Check for working C compiler using: Xcode
-- Check for working C compiler using: Xcode -- broken
....

To help that, I set
export
SDKROOT=/Applications/Xcode-4.6.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.8.sdk
then try again with a clean build dir to get:
-- The C compiler identification is unknown
-- The CXX compiler identification is unknown
-- Check for working C compiler using: Xcode
-- Check for working C compiler using: Xcode -- works

The compiler id test failed.
I go into CMakeFiles/<version>/CompilerIdC and run xcodebuild -project
CompierIdC.xcodeproj and it fails to link because of this error:
ld: library not found for -lcrt1.10.6.o

If the xcodeproj is manually edited to include
SDKROOT =
"/Applications/Xcode-4.6.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.8.sdk";

Then the problem goes away.


Using the Makefile generator didn't have these issues.
I could set the environment variables CC, CXX, SDKROOT and things worked fine.
CMake knows how to avoid the linker error about not finding -lcrt1.10.6.o when
using the Makefile generator by using -sysroot on the compiler id test.  The
xcode generator needs the same.

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Issue History 
Date Modified    Username       Field                    Change               
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2013-11-16 18:24 Clinton StimpsonNew Issue                                    
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