How do you set CMAKE_C_COMPILER and CMAKE_CXX_COMPILER for building Assimp for iOS?

Solution 1:

Option 1:

You can set CMake variables at command line like this:

cmake -D CMAKE_C_COMPILER="/path/to/your/c/compiler/executable" -D CMAKE_CXX_COMPILER "/path/to/your/cpp/compiler/executable" /path/to/directory/containing/CMakeLists.txt

See this to learn how to create a CMake cache entry.


Option 2:

In your shell script build_ios.sh you can set environment variables CC and CXX to point to your C and C++ compiler executable respectively, example:

export CC=/path/to/your/c/compiler/executable
export CXX=/path/to/your/cpp/compiler/executable
cmake /path/to/directory/containing/CMakeLists.txt

Option 3:

Edit the CMakeLists.txt file of "Assimp": Add these lines at the top (must be added before you use project() or enable_language() command)

set(CMAKE_C_COMPILER "/path/to/your/c/compiler/executable")
set(CMAKE_CXX_COMPILER "/path/to/your/cpp/compiler/executable")

See this to learn how to use set command in CMake. Also this is a useful resource for understanding use of some of the common CMake variables.


Here is the relevant entry from the official FAQ: https://gitlab.kitware.com/cmake/community/wikis/FAQ#how-do-i-use-a-different-compiler

Solution 2:

The cc and cxx is located inside /Applications/Xcode.app. This should find the right paths

export CXX=`xcrun -find c++`
export CC=`xcrun -find cc`

Solution 3:

SOLUTIONS

  1. Sometimes the project is created before installing g++. So install g++ first and then recreate your project. This worked for me.
  2. Paste the following line in CMakeCache.txt: CMAKE_CXX_COMPILER:FILEPATH=/usr/bin/c++

Note the path to g++ depends on OS. I have used my fedora path obtained using which g++