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Internal LLVM syntax errors when following Pass tutorial using CMake

I am attempting to follow the tutorial here for developing a "Hello, World" LLVM pass - I am using the guidelines linked by that tutorial here for doing so out of the LLVM source directory. However, when I attempt to follow this tutorial, CMake reports a number of errors internal to LLVM itself.

I have the following directory structure:

HelloWorld/ CMakeLists.txt HelloWorld/ CMakeLists.txt HelloWorld.cpp

My HelloWorld.cpp, and the two CMakeLists.txt are copy and pasted directly from the tutorials linked to above.

I run CMake HelloWorld and it successfully generates a CMake configuration. However, when I run make. I get numerous errors reported from within the LLVM codebase itself. 

[ 50%] Building CXX object CMakeFiles/LLVMPassName.dir/Vectorize.cpp.o
In file included from /Volumes/andromeda/HelloWorld/HelloWorld.cpp:1:
In file included from /usr/local/Cellar/llvm/3.6.2/include/llvm/Pass.h:377:
In file included from /usr/local/Cellar/llvm/3.6.2/include/llvm/PassSupport.h:27:
In file included from /usr/local/Cellar/llvm/3.6.2/include/llvm/PassRegistry.h:20:
In file included from /usr/local/Cellar/llvm/3.6.2/include/llvm-c/Core.h:18:
In file included from /usr/local/Cellar/llvm/3.6.2/include/llvm-c/Support.h:17:
/usr/local/Cellar/llvm/3.6.2/include/llvm/Support/DataTypes.h:57:3: error: "Must #define
      __STDC_LIMIT_MACROS before #including Support/DataTypes.h"
# error "Must #define __STDC_LIMIT_MACROS before #including Support/DataTypes.h"
  ^
/usr/local/Cellar/llvm/3.6.2/include/llvm/Support/DataTypes.h:61:3: error: "Must #define
      __STDC_CONSTANT_MACROS before "         "#including Support/DataTypes.h"
# error "Must #define __STDC_CONSTANT_MACROS before " \

The list goes on and on and all of them refer to errors in LLVM header files. This is a clean install of LLVM using Homebrew. To get linking to work, I had to set CPLUS_INCLUDE_PATH to the Homebrew include directory for LLVM.

My first thought was that CMake was attempting to use a different compiler (Clang vs. GCC or vice versa), but setting CMAKE_CXX_COMPILER to point to either my clang or g++ installation did not help.

Does anyone have any ideas for what might be the problem here?

After following the link provided by @oak in the comments, I was able to get rid of the first two Support/DataType errors. However, many of the errors still remain. 

In file included from /usr/local/Cellar/llvm/3.6.2/include/llvm/Pass.h:377:
In file included from /usr/local/Cellar/llvm/3.6.2/include/llvm/PassSupport.h:27:
In file included from /usr/local/Cellar/llvm/3.6.2/include/llvm/PassRegistry.h:21:
/usr/local/Cellar/llvm/3.6.2/include/llvm/ADT/DenseMap.h:543:63: error: a space is required
      between consecutive right angle brackets (use '> >')
          typename BucketT = detail::DenseMapPair<KeyT, ValueT>>
                                                              ^
/usr/local/Cellar/llvm/3.6.2/include/llvm/ADT/DenseMap.h:694:63: error: a space is required
      between consecutive right angle brackets (use '> >')
          typename BucketT = detail::DenseMapPair<KeyT, ValueT>>
Solution

  • So, after much research, it turns out that there is an inconsistency with how LLVM and CMake support out-of-source builds. The LLVM binaries are built with -fno-rtti, so CMake will complain about missing symbols unless it is also uses -fno-rtti when compiling the LLVM pass.

    I fixed all of my troubles (including those solved by the temporary fix proposed by Oak) by adding SET(CMAKE_CXX_FLAGS "-Wall -fno-rtti") to my CMakeLists.txt file in the innermost directory.

    This was inspired by this question also on StackOverflow.