Windows: unable to find launch-cxx

[thelartians]

Windows: unable to find launch-cxx

[abdes]

The error does not come from ccache. It comes from the fact that you are using a wrapper shell script to invoke ccache on a windows platform. Here is what I do to work around this:

find_program(CCACHE_TOOL_PATH ccache)

if(NOT WIN32 AND USE_CCACHE AND CCACHE_TOOL_PATH)
  message(STATUS "Using ccache (${CCACHE_TOOL_PATH}) (via wrapper).")
  # see https://github.com/TheLartians/Ccache.cmake enables CCACHE support through
  # the USE_CCACHE flag possible values are: YES, NO or equivalent
  cpmaddpackage("gh:TheLartians/[email protected]")
elseif(WIN32 AND USE_CCACHE AND CCACHE_TOOL_PATH)
  set(CMAKE_C_COMPILER_LAUNCHER ${CCACHE_TOOL_PATH} CACHE STRING "" FORCE)
  set(CMAKE_CXX_COMPILER_LAUNCHER ${CCACHE_TOOL_PATH} CACHE STRING "" FORCE)
  message(STATUS "Using ccache (${CCACHE_TOOL_PATH}).")
endif()

[cristianadam]

I have my own fork of ccache which adds support for Visual C++. This works only in release mode. I haven't managed to finish pushing it upstream ccache/ccache#506

At https://github.com/cristianadam/HelloWorld I have a project using the binary artifacts from my ccache fork to build for Linux, Windows MinGW / MSVC, macOS.

Qt Creator is a bigger project that uses this https://github.com/qt-creator/qt-creator/actions.

[TheLartians]

Hey, thanks for the issue! Unfortunately I don't have access to a windows system atm, so I can't reproduce the bug locally. Does it still occur in version 1.2.2, which uses absolute paths to the scripts?

Also, it might be a good idea to adapt Ccache.cmake for better Windows support, e.g. by adding PowerShell scripts or changing the CMake logic to set the RULE_LAUNCH_COMPILE argument (in case it's supported on windows, which needs to be tested).

[erri120]

1.2.2 also fails.

Ninja fails with this error:

[0/2] Re-checking globbed directories...
ninja: fatal: CreateProcess: %1 is not a valid Win32 application.

[TheLartians]

Ok, thanks for testing! Yeah indeed seems like we need a separate conditional branch if we want to support windows targets. Unfortunately, I couldn't find too much infos on using CMake to activate Ccache on Windows, so if you have any leads or even a PR fixing it, it would be great!

[craigscott-crascit]

@cristianadam may be able to offer some insights. I believe he was working on Windows support for ccache at one point.

[Banderi]

The error does not come from ccache. It comes from the fact that you are using a wrapper shell script to invoke ccache on a windows platform. Here is what I do to work around this:

find_program(CCACHE_TOOL_PATH ccache)

if(NOT WIN32 AND USE_CCACHE AND CCACHE_TOOL_PATH)
  message(STATUS "Using ccache (${CCACHE_TOOL_PATH}) (via wrapper).")
  # see https://github.com/TheLartians/Ccache.cmake enables CCACHE support through
  # the USE_CCACHE flag possible values are: YES, NO or equivalent
  cpmaddpackage("gh:TheLartians/[email protected]")
elseif(WIN32 AND USE_CCACHE AND CCACHE_TOOL_PATH)
  set(CMAKE_C_COMPILER_LAUNCHER ${CCACHE_TOOL_PATH} CACHE STRING "" FORCE)
  set(CMAKE_CXX_COMPILER_LAUNCHER ${CCACHE_TOOL_PATH} CACHE STRING "" FORCE)
  message(STATUS "Using ccache (${CCACHE_TOOL_PATH}).")
endif()

This worked on my end. Thank you!
Hopefully a proper fix can be implemented soon!