Backport tool

A tool to transform C++11 language elements to C++03 compatible form.

Usage

There are two different ways for transformation:

• If only one file is transformed it is enough to specify the path of the file.
• If more files or a whole project is transformed, a compile_command.json file must be created which specifies the compilation information about all files. In this case the following argument can be used:
  • Command line option -p can be used to specify the directory where the compile_commands.json file is stored.
  • Command line option -include can be used to specify the files being transformed.
    • If there is only one file to transform, then the -include option should contain the path of the file.
    • If there are multiple files to transform, then the -include option should contain the path of the directory. All source files in the directory (which are also listed in the compile_commands.json) will be transformed.
  • It is possible to use -include-from instead of -include which should contain the path of a text file. This text file lists all the source files that we want to transform.

Commands line arguments

• -summary: During transformation, the tool will show a summary about the number of transforms performed by each step.
• -no-db: Turns off the database used for incremental transformation.
• -in-place: The tool overwrites the original files instead of copying and modifying files in a temporary directory.
• Select transformations: You can select specific transformations which will be performed. If you don't use this argument, the tool will perform all the transformations that are implemented. (Note: Some transformations expect that other ones are already finished. So if you are trying to run some transformations individually, you can get unexpected results.)
  • -modify-auto: Transforms template functions with auto return type.
  • -instantiate-template: Specializing templates containing template-dependent auto expressions.
  • -replace-lambda: Transforms lambda expressions.
  • -replace-member-init: Transforms member field initializators.
  • -replace-for-range: Transforms for-range style for loops.
  • -deduce-auto: Deduces variables with auto type.
  • -remove-auto: Removes those template-dependent auto expressions that are in a class that hasn't been instantiated and that are in a method that has not been called.
• Serializing transformations:
  • -serialize-replacements: The tool writes transformations to a file instead of replacing them in the source files. It can be used only when at least one transform is selected to be performed.
  • -serialize-dir: Specifies the directory, where the files (that contain the serialized transformations) will be stored.

Getting Started

Dependencies

• LLVM Release 3.6
• Clang Release 3.6
• Clang extra tools 3.6
• cmake 3

Supported platforms

• Linux
• Windows

Building the source code

1. Checkout LLVM 3.6 from repository

    svn co http://llvm.org/svn/llvm-project/llvm/branches/release_36/ llvm
   

2. Checkout Clang 3.6 from repository

    cd llvm/tools
    svn co http://llvm.org/svn/llvm-project/cfe/branches/release_36/ clang
   

3. Checkout Clang extra tools from repository

    cd clang/tools
    svn co http://llvm.org/svn/llvm-project/clang-tools-extra/branches/release_36/ extra
   

4. Checkout backport tool into extra directory

    cd extra
    git clone https://github.com/sed-szeged/cppbackport.git
    cp -R cppbackport/backport backport
   

5. Edit CMakeLists.txt in extra directory.

    add_subdirectory(cppbackport)
   

6. Applying patch files

    cd ../..
    patch -p0 < tools/extra/cppbackport/ClangPatch/unknownattrib.patch
    patch -p0 < tools/extra/cppbackport/ClangPatch/ignoremsasm.patch
    patch -p0 < tools/extra/cppbackport/ClangPatch/template-template-parameter-namespace-print-fix.patch
    patch -p0 < tools/extra/cppbackport/ClangPatch/ASTMatchFinder.cpp.patch
   
    cd lib/Sema
    patch -p0 < ../../tools/extra/cppbackport/ClangPatch/llvm.tools.clang.lib.Sema.SemaTemplateInstantiateDecl.cpp.patch
    patch -p0 < ../../tools/extra/cppbackport/ClangPatch/llvm.tools.clang.lib.Sema.Sema.cpp.patch
   

7. Create build directory and run cmake.

    cd ../../..  # To the parent dir of llvm/
    mkdir build
    cd build
    cmake ../llvm -DCMAKE_BUILD_TYPE=Release
    make
   

Authors and Contributors

Backport tool is created and maintained by the Department of Software Engineering, University of Szeged.

Contribution

If you would like to contribute to the project, create an issue at our GitHub page or send a pull request. Every contribution is welcome!