MantisBT - ITK
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IDProjectCategoryView StatusDate SubmittedLast Update
0006267ITKpublic2008-01-23 09:512008-03-02 12:17
ReporterSean McBride 
Assigned ToBill Lorensen 
PrioritynormalSeverityminorReproducibilityalways
StatusclosedResolutionfixed 
PlatformMac OS XOSMac OS XOS Version10.5
Product Version 
Target VersionFixed in Version 
Resolution Date
Sprint
Sprint Status
Summary0006267: ITK should not force -no-cpp-precomp compiler flag on Mac OS X
DescriptionIn ITK's main CMakeLists.txt there is the following:

 IF(APPLE)
   SET(ITK_REQUIRED_C_FLAGS "${ITK_REQUIRED_C_FLAGS} -no-cpp-precomp")
   SET(ITK_REQUIRED_CXX_FLAGS "${ITK_REQUIRED_CXX_FLAGS} -no-cpp-precomp")
   SET(ITK_REQUIRED_CXX_FLAGS "${ITK_REQUIRED_CXX_FLAGS} -Wno-long-double")
 ENDIF(APPLE)

I would like to request that the "-no-cpp-precomp" be removed. Basically, it is an obsolete flag that is only in Apple's gcc and not the FSF gcc. It's not even in the man page.

The reason I make this request is that in beta versions of Apple's gcc 4.2 the flag is gone, and so ITK cannot be built the way it is now. If I remove the flag, ITK builds fine.

This link has more info:
http://gcc.gnu.org/ml/gcc-prs/2003-05/msg01546.html [^]

The only reason I see to keep it is if it is absolutely needed for some really old Apple gcc, like 2.95. And even then it would need to be conditionalised.

The flag was added to ITK at this point:
http://www.itk.org/cgi-bin/viewcvs.cgi/CMakeLists.txt?root=Insight&r1=1.132&r2=1.133 [^]

Steps To Reproduce
Additional Information
TagsNo tags attached.
Relationships
related to 0011336closed Brad King itkCheckCXXAcceptsFlags only works in English 
Attached Files
Issue History
Date ModifiedUsernameFieldChange
2008-01-23 09:51Sean McBrideNew Issue
2008-02-07 13:37Sean McBrideDescription Updated
2008-02-09 23:56Bill HoffmanNote Added: 0010442
2008-02-10 08:43Bill LorensenNote Added: 0010444
2008-02-10 08:44Bill LorensenNote Added: 0010445
2008-02-10 08:44Bill LorensenStatusnew => feedback
2008-02-11 09:56Sean McBrideNote Added: 0010447
2008-02-11 10:27Bill HoffmanNote Added: 0010448
2008-02-11 13:32Bill LorensenNote Added: 0010452
2008-02-11 13:47Sean McBrideNote Added: 0010454
2008-02-13 10:19Bill LorensenStatusfeedback => assigned
2008-02-13 10:19Bill LorensenAssigned To => Bill Lorensen
2008-02-13 10:23Bill LorensenStatusassigned => resolved
2008-02-13 10:23Bill LorensenResolutionopen => fixed
2008-02-13 10:23Bill LorensenNote Added: 0010472
2008-02-13 13:17Sean McBrideStatusresolved => feedback
2008-02-13 13:17Sean McBrideResolutionfixed => reopened
2008-02-13 13:17Sean McBrideNote Added: 0010480
2008-02-13 13:30Sean McBrideStatusfeedback => confirmed
2008-02-14 14:42Bill LorensenStatusconfirmed => closed
2008-02-14 14:42Bill LorensenResolutionreopened => fixed
2008-03-02 12:16Bill LorensenStatusclosed => resolved
2008-03-02 12:16Bill LorensenNote Added: 0010681
2008-03-02 12:17Bill LorensenStatusresolved => closed
2008-03-02 12:17Bill LorensenNote Added: 0010682
2010-11-03 09:46Brad KingRelationship addedrelated to 0011336

Notes
(0010442)
Bill Hoffman   
2008-02-09 23:56   
I am guessing that what ever version of gcc/Mac OS that shipped in 2003 when I made that change did not compile ITK without it. I am sure if it is removed it will break ITK for that version of Mac OS/gcc, and most likely some other versions. So, I would suggest a try_compile that detects if gcc accepts the flag or not, and then it should work for both old and new gcc/Mac Os versions.
(0010444)
Bill Lorensen   
2008-02-10 08:43   
We could use CheckCXXCompilerFlag.cmake
IF(APPLE)
  INCLUDE(${CMAKE_ROOT}/Modules/CheckCXXCompilerFlag.cmake)
  CHECK_CXX_COMPILER_FLAG("-no-cpp-precomp" CXX_HAS_PRECOMP_FLAG)
  IF(CXX_HAS_PRECOMP_FLAG)
    SET(ITK_REQUIRED_CXX_FLAGS "${ITK_REQUIRED_CXX_FLAGS} -no-cpp-precomp")
  ENDIF(CXX_HAS_PRECOMP_FLAG)

  INCLUDE(${CMAKE_ROOT}/Modules/CheckCCompilerFlag.cmake)
  CHECK_C_COMPILER_FLAG("-no-cpp-precomp" C_HAS_PRECOMP_FLAG)
  IF(C_HAS_PRECOMP_FLAG)
    SET(ITK_REQUIRED_C_FLAGS "${ITK_REQUIRED_C_FLAGS} -no-cpp-precomp")
  ENDIF(C_HAS_PRECOMP_FLAG)
ENDIF(APPLE)
(0010445)
Bill Lorensen   
2008-02-10 08:44   
Sean,

Can you try out the cmake code I added to the note?

Bill
(0010447)
Sean McBride   
2008-02-11 09:56   
Bill & Bill,

This looks like it should work, but for some reason with gcc 4.2 I'm still getting into the IF that uses the flag (confirmed by commenting out the SET(ITK_REQUIRED_CXX_FLAGS "${ITK_REQUIRED_CXX_FLAGS} -no-cpp-precomp") line).

Here is how 4.2 reacts to the flag:

sean$ /usr/bin/g++-4.2 -no-cpp-precomp
i686-apple-darwin9-g++-4.2.1: unrecognized option '-no-cpp-precomp'
i686-apple-darwin9-g++-4.2.1: no input files

BTW, gcc 4.0 (current in Xcode 3) builds ITK fine with or without -no-cpp-precomp. For older gccs I have no idea.
(0010448)
Bill Hoffman   
2008-02-11 10:27   
OK, well, we have to get the try compile to work. Can you look at CMakeOutput.log and CMakeError.log and try to figure out why the try compile did not work? What is the value of CXX_HAS_PRECOMP_FLAG in your cache? Can you try a very simple CMakeLists.txt file, one with something like this:

INCLUDE(CheckCXXCompilerFlag)
  CHECK_CXX_COMPILER_FLAG("-no-cpp-precomp" CXX_HAS_PRECOMP_FLAG)
  IF(CXX_HAS_PRECOMP_FLAG)
    SET(ITK_REQUIRED_CXX_FLAGS "${ITK_REQUIRED_CXX_FLAGS} -no-cpp-precomp")
  ENDIF(CXX_HAS_PRECOMP_FLAG)

  INCLUDE(CheckCCompilerFlag)
  CHECK_C_COMPILER_FLAG("-no-cpp-precomp" C_HAS_PRECOMP_FLAG)
  IF(C_HAS_PRECOMP_FLAG)
    SET(ITK_REQUIRED_C_FLAGS "${ITK_REQUIRED_C_FLAGS} -no-cpp-precomp")
  ENDIF(C_HAS_PRECOMP_FLAG)
  SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${ITK_REQUIRED_CXX_FLAGS}")
  SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${ITK_REQUIRED_C_FLAGS}")
add_library(foo foo.cxx bar.c)
(foo.cxx and foo.c can be empty files.
(0010452)
Bill Lorensen   
2008-02-11 13:32   
Just tried Bill's suggested test. The value of CXX_HAS_PRECOMP_FLAG) is 1.
Here is CMakeOutput.log

Performing C++ SOURCE FILE Test CXX_HAS_PRECOMP_FLAG succeded with the following output:
/usr/bin/gmake -f CMakeFiles/cmTryCompileExec.dir/build.make CMakeFiles/cmTryCompileExec.dir/build
gmake[1]: Entering directory `/home/lorensen/Projects/CommandLineAPI/foo-linux/CMakeFiles/CMakeTmp'
/usr/bin/cmake -E cmake_progress_report /home/lorensen/Projects/CommandLineAPI/foo-linux/CMakeFiles/CMakeTmp/CMakeFiles 1
Building CXX object CMakeFiles/cmTryCompileExec.dir/src.o
/usr/bin/c++ -DCXX_HAS_PRECOMP_FLAG -no-cpp-precomp -o CMakeFiles/cmTryCompileExec.dir/src.o -c /home/lorensen/Projects/CommandLineAPI/foo-linux/CMakeFiles/CMakeTmp/src.cxx
c++: unrecognized option '-no-cpp-precomp'
Linking CXX executable cmTryCompileExec
/usr/bin/cmake -P CMakeFiles/cmTryCompileExec.dir/cmake_clean_target.cmake
/usr/bin/c++ -DCXX_HAS_PRECOMP_FLAG -fPIC "CMakeFiles/cmTryCompileExec.dir/src.o" -o cmTryCompileExec -rdynamic
gmake[1]: Leaving directory `/home/lorensen/Projects/CommandLineAPI/foo-linux/CMakeFiles/CMakeTmp'

Source file was:
int main() { return 0;}
Performing C SOURCE FILE Test C_HAS_PRECOMP_FLAG succeded with the following output:
/usr/bin/gmake -f CMakeFiles/cmTryCompileExec.dir/build.make CMakeFiles/cmTryCompileExec.dir/build
gmake[1]: Entering directory `/home/lorensen/Projects/CommandLineAPI/foo-linux/CMakeFiles/CMakeTmp'
/usr/bin/cmake -E cmake_progress_report /home/lorensen/Projects/CommandLineAPI/foo-linux/CMakeFiles/CMakeTmp/CMakeFiles 1
Building C object CMakeFiles/cmTryCompileExec.dir/src.o
/usr/bin/gcc -DC_HAS_PRECOMP_FLAG -no-cpp-precomp -o CMakeFiles/cmTryCompileExec.dir/src.o -c /home/lorensen/Projects/CommandLineAPI/foo-linux/CMakeFiles/CMakeTmp/src.c
gcc: unrecognized option '-no-cpp-precomp'
Linking C executable cmTryCompileExec
/usr/bin/cmake -P CMakeFiles/cmTryCompileExec.dir/cmake_clean_target.cmake
/usr/bin/gcc -DC_HAS_PRECOMP_FLAG -fPIC "CMakeFiles/cmTryCompileExec.dir/src.o" -o cmTryCompileExec -rdynamic
gmake[1]: Leaving directory `/home/lorensen/Projects/CommandLineAPI/foo-linux/CMakeFiles/CMakeTmp'
(0010454)
Sean McBride   
2008-02-11 13:47   
With gcc 4.0 I get:

Performing C++ SOURCE FILE Test CXX_HAS_PRECOMP_FLAG succeded with the following output:
/usr/bin/make -f CMakeFiles/cmTryCompileExec.dir/build.make CMakeFiles/cmTryCompileExec.dir/build
/usr/local/bin/cmake -E cmake_progress_report /Users/sean/Desktop/Test/bin4.0/CMakeFiles/CMakeTmp/CMakeFiles 1
Building CXX object CMakeFiles/cmTryCompileExec.dir/src.o
/usr/bin/c++ -DCXX_HAS_PRECOMP_FLAG -no-cpp-precomp -o CMakeFiles/cmTryCompileExec.dir/src.o -c /Users/sean/Desktop/Test/bin4.0/CMakeFiles/CMakeTmp/src.cxx
Linking CXX executable cmTryCompileExec
/usr/local/bin/cmake -P CMakeFiles/cmTryCompileExec.dir/cmake_clean_target.cmake
/usr/bin/c++ -DCXX_HAS_PRECOMP_FLAG -headerpad_max_install_names -fPIC "CMakeFiles/cmTryCompileExec.dir/src.o" -o cmTryCompileExec

With gcc 4.2 I get:

Performing C++ SOURCE FILE Test CXX_HAS_PRECOMP_FLAG succeded with the following output:
/usr/bin/make -f CMakeFiles/cmTryCompileExec.dir/build.make CMakeFiles/cmTryCompileExec.dir/build
/usr/local/bin/cmake -E cmake_progress_report /Users/sean/Desktop/Test/bin4.2/CMakeFiles/CMakeTmp/CMakeFiles 1
Building CXX object CMakeFiles/cmTryCompileExec.dir/src.o
/usr/bin/g++-4.2 -DCXX_HAS_PRECOMP_FLAG -no-cpp-precomp -o CMakeFiles/cmTryCompileExec.dir/src.o -c /Users/sean/Desktop/Test/bin4.2/CMakeFiles/CMakeTmp/src.cxx
i686-apple-darwin9-g++-4.2.1: unrecognized option '-no-cpp-precomp'
Linking CXX executable cmTryCompileExec
/usr/local/bin/cmake -P CMakeFiles/cmTryCompileExec.dir/cmake_clean_target.cmake
/usr/bin/g++-4.2 -DCXX_HAS_PRECOMP_FLAG -headerpad_max_install_names -fPIC "CMakeFiles/cmTryCompileExec.dir/src.o" -o cmTryCompileExec

The "unrecognized option '-no-cpp-precomp'" is only in the latter, as expected. But should the latter say "succeded with the following output"? Is it not detecting the failing compilation?
(0010472)
Bill Lorensen   
2008-02-13 10:23   
Created a new macro: itkCheckCXXAcceptsFlags.
http://www.itk.org/cgi-bin/viewcvs.cgi/CMake/itkCheckCXXAcceptsFlags.cmake?rev=1.1&root=Insight&sortby=date&view=log [^]

This macro scans the output of the compiler to look for warnings about unrecognized flags.

Also updated CMakeLists.txt to use the macro to check the -no-cpp-precomp flag on the MAC OS X compiler.
http://www.itk.org/cgi-bin/viewcvs.cgi/CMakeLists.txt?rev=1.281&root=Insight&view=log [^]
(0010480)
Sean McBride   
2008-02-13 13:17   
Turns out -Wno-long-double is also removed. So I've done the analogous fix. All is well now.

Please review this:

/cvsroot/Insight/Insight/CMakeLists.txt,v <-- CMakeLists.txt
new revision: 1.282; previous revision: 1.281
(0010681)
Bill Lorensen   
2008-03-02 12:16   
Sean's additional changes to handle -Wno-long-double are working.
(0010682)
Bill Lorensen   
2008-03-02 12:17   
All platforms seem to be handled OK.