[cmake-developers] [CMake 0013897]: Cross-compiling from Windows with a Linux-GCC toolchain exceeds max command line length during linking

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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http://public.kitware.com/Bug/view.php?id=13897 
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Reported By:                Eric Gross
Assigned To:                
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Project:                    CMake
Issue ID:                   13897
Category:                   CMake
Reproducibility:            always
Severity:                   minor
Priority:                   normal
Status:                     new
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Date Submitted:             2013-02-07 16:21 EST
Last Modified:              2013-02-07 16:21 EST
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Summary:                    Cross-compiling from Windows with a Linux-GCC
toolchain exceeds max command line length during linking
Description: 
When compiling using GCC on Windows as a non-cross-compile, CMake has code in
the platform files for using a response file to pass the objects to GCC's
linker. When cross-compiling to a Linux toolchain, this workaround is not used.
I was hitting this issue at around the 200-300 file count.

It seems that GCC supports the usage of response files across all OSes.
Additionally, it seems that there are some cases that on certain Linux
configurations (compiling natively) that they can run into the same issue as
Windows. I believe CMake should use response files under the situation I am
seeing (cross-compiling on Windows) and perhaps more universally.



Steps to Reproduce: 
I cross-compiled the GenICam GenAPI reference implementation from Windows to an
ARM/Linux target. GenApi's source includes components Xerces and Xalan, both
which have hundreds of files and hit this error. The error shown is an
unterminated string in sh.exe because the line is truncated.



Additional Information: 
To work around this I added the following into the macro section of
Linux-GNU.cmake (copied from the Windows version of that file):

    set(CMAKE_${lang}_USE_RESPONSE_FILE_FOR_OBJECTS 1)
    set(CMAKE_${lang}_USE_RESPONSE_FILE_FOR_INCLUDES 1)


  # We prefer "@" for response files but it is not supported by gcc 3.
  execute_process(COMMAND ${CMAKE_${lang}_COMPILER} --version OUTPUT_VARIABLE
_ver ERROR_VARIABLE _ver)
  if("${_ver}" MATCHES "\\(GCC\\) 3\\.")
    if("${lang}" STREQUAL "Fortran")
      # The GNU Fortran compiler reports an error:
      #   no input files; unwilling to write output files
      # when the response file is passed with "-Wl,@".
      set(CMAKE_Fortran_USE_RESPONSE_FILE_FOR_OBJECTS 0)
    else()
      # Use "-Wl,@" to pass the response file to the linker.
      set(CMAKE_${lang}_RESPONSE_FILE_LINK_FLAG "-Wl,@")
    endif()
    # The GNU 3.x compilers do not support response files (only linkers).
    set(CMAKE_${lang}_USE_RESPONSE_FILE_FOR_INCLUDES 0)
  elseif(CMAKE_${lang}_USE_RESPONSE_FILE_FOR_OBJECTS)
    # Use "@" to pass the response file to the front-end.
    set(CMAKE_${lang}_RESPONSE_FILE_LINK_FLAG "@")
  endif()  
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Issue History 
Date Modified    Username       Field                    Change               
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2013-02-07 16:21 Eric Gross     New Issue                                    
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