pixi: Add some ccache configuration

Author: jorisv

development/scripts/pixi/activation.sh

@@ -20,6 +20,9 @@ then
   # On GNU/Linux, I don't know if these flags are mandatory with g++ but
   # it allow to use clang++ as compiler
   export LDFLAGS="-Wl,-rpath,$CONDA_PREFIX/lib -Wl,-rpath-link,$CONDA_PREFIX/lib -L$CONDA_PREFIX/lib"
+  # Conda compiler is named x86_64-conda-linux-gnu-c++, ccache can't resolve it
+  # (https://ccache.dev/manual/latest.html#config_compiler_type)
+  export CCACHE_COMPILERTYPE=gcc
 fi
 # Without -isystem, some LSP can't find headers
 export EIGENPY_CXX_FLAGS="$CXXFLAGS -isystem $CONDA_PREFIX/include"

pixi.toml

@@ -63,6 +63,8 @@ CMAKE_CXX_COMPILER_LAUNCHER = "ccache"
 CMAKE_EXPORT_COMPILE_COMMANDS = "ON"
 # Activate color output with Ninja
 CMAKE_COLOR_DIAGNOSTICS = "ON"
+# Help ccache manage generated files and PCH (https://ccache.dev/manual/latest.html#_precompiled_headers)
+CCACHE_SLOPPINESS = "include_file_ctime,include_file_mtime,pch_defines,time_macros"
 
 [tasks]
 # We must avoid to set CMAKE_CXX_FLAGS because of WIN32