missing include in popen.cpp

[mauro80]

Bug category

• [ x] bug - compilation error
• bug - compilation warning
• bug - runtime error
• bug - runtime warning
• bug - logic error

Describe the bug

Linux, LLVM 22. Likely new clang skips some includes, that were previously included automatically. There is a missing #include <cstdlib> in source/matplot/util/popen.cpp

Steps to Reproduce

# Your steps go here
cmake ..  -G Ninja -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++  -DMATPLOTPP_BUILD_EXAMPLES=OFF  -DMATPLOTPP_BUILD_TESTS=OFF  -DMATPLOTPP_BUILD_SHARED_LIBS=ON

Output

Details

[13/45] Building CXX object source/matplot/CMakeFiles/matplot.dir/util/popen.cpp.o
FAILED: [code=1] source/matplot/CMakeFiles/matplot.dir/util/popen.cpp.o 
# personal paths
source/matplot/CMakeFiles/matplot.dir/util/popen.cpp.o.d -o source/matplot/CMakeFiles/matplot.dir/util/popen.cpp.o -c ./matplotplusplus/source/matplot/util/popen.cpp
./matplot/util/popen.cpp:152:14: error: no type named 'exit' in namespace 'std'
  152 |         std::exit(EXIT_FAILURE);
      |         ~~~~~^
1 error generated.

Platform

• [x ] cross-platform issue - linux
• cross-platform issue - windows
• cross-platform issue - macos

Environment Details:

• OS: Arch
• OS Version: linux 6.18
• Compiler: clang++ (works in gcc_
• Compiler version: clang version 22.0.0git (https://github.com/llvm/llvm-project.git 367e3889fabcc3dcd3ee2d664d652ab6ec26854b) Target: x86_64-unknown-linux-gnu Thread model: posix

Additional context

Using libc++ from LLVM.