qtbase/cmake/QtPublicWasmToolchainHelpers.cmake
Morten Sørvig b8bcf6b883 wasm: handle unable to determine emcc versiopn
It can happen that we are not able to determine which
Emscripten version Qt is built with, for example if
the detection code runs at a time when qconfig.h has
not been created yet.

In that case skip printing a warning since we are not
able to offer a sensible recommendation.

This fixes Qt configure when building for shared libraries,
where we would previously print this warning several
times:

  Qt Wasm built with Emscripten version:
  You are using Emscripten version: 3.1.50
  The recommended version of Emscripten for this Qt is: 3.1.50
  This may not work correctly

Change-Id: Ie15300e89c0e4b6f22650e662dd30fd32828e60c
Reviewed-by: Morten Johan Sørvig <morten.sorvig@qt.io>
2024-05-16 18:49:25 +02:00

107 lines
4.5 KiB
CMake

# Copyright (C) 2022 The Qt Company Ltd.
# SPDX-License-Identifier: BSD-3-Clause
# Assuming EMSDK == /path/emsdk
#
# Then we expect /path/emsdk/.emscripten file to contain the following line
# EMSCRIPTEN_ROOT = emsdk_path + '/upstream/emscripten'
#
# then we set out_var to '/upstream/emscripten', so it's not a full path
function(__qt_internal_get_emroot_path_suffix_from_emsdk_env out_var)
# Query EMSCRIPTEN_ROOT path.
file(READ "$ENV{EMSDK}/.emscripten" ver)
string(REGEX MATCH "EMSCRIPTEN_ROOT.*$" EMROOT "${ver}")
string(REGEX MATCH "'([^' ]*)'" EMROOT2 "${EMROOT}")
string(REPLACE "'" "" EMROOT_PATH "${EMROOT2}")
set(${out_var} "${EMROOT_PATH}" PARENT_SCOPE)
endfunction()
function(__qt_internal_get_emscripten_cmake_toolchain_file_path_from_emsdk_env emroot_path out_var)
set(wasm_toolchain_file "$ENV{EMSDK}/${emroot_path}/cmake/Modules/Platform/Emscripten.cmake")
set(${out_var} "${wasm_toolchain_file}" PARENT_SCOPE)
endfunction()
function(__qt_internal_query_emsdk_version emroot_path is_fatal out_var)
# get emscripten version
if(CMAKE_HOST_SYSTEM_NAME STREQUAL "Windows")
set(EXECUTE_COMMANDPATH "$ENV{EMSDK}/${emroot_path}/emcc.bat")
else()
set(EXECUTE_COMMANDPATH "$ENV{EMSDK}/${emroot_path}/emcc")
endif()
file(TO_CMAKE_PATH "${EXECUTE_COMMANDPATH}" EXECUTE_COMMAND)
execute_process(COMMAND ${EXECUTE_COMMAND} --version
OUTPUT_VARIABLE emOutput
OUTPUT_STRIP_TRAILING_WHITESPACE
ERROR_VARIABLE emrun_error
RESULT_VARIABLE result)
message(DEBUG "emcc --version output: ${emOutput}")
if(NOT emOutput)
if(is_fatal)
message(FATAL_ERROR
"Couldn't determine Emscripten version from running ${EXECUTE_COMMAND} --version. "
"Error: ${emrun_error}")
endif()
set(${out_var} "" PARENT_SCOPE)
else()
string(REGEX MATCH "[0-9]+\\.[0-9]+\\.[0-9]+" CMAKE_EMSDK_REGEX_VERSION "${emOutput}")
set(${out_var} "${CMAKE_EMSDK_REGEX_VERSION}" PARENT_SCOPE)
endif()
endfunction()
function(__qt_internal_get_emcc_recommended_version out_var)
# This version of Qt needs this version of emscripten.
set(QT_EMCC_RECOMMENDED_VERSION "3.1.50")
set(${out_var} "${QT_EMCC_RECOMMENDED_VERSION}" PARENT_SCOPE)
endfunction()
function(__qt_internal_show_error_no_emscripten_toolchain_file_found_when_building_qt)
message(FATAL_ERROR
"Cannot find the toolchain file Emscripten.cmake. "
"Please specify the toolchain file with -DCMAKE_TOOLCHAIN_FILE=<file> "
"or provide a path to a valid emscripten installation via the EMSDK "
"environment variable.")
endfunction()
function(__qt_internal_show_error_no_emscripten_toolchain_file_found_when_using_qt)
message(FATAL_ERROR
"Cannot find the toolchain file Emscripten.cmake. "
"Please specify the toolchain file with -DQT_CHAINLOAD_TOOLCHAIN_FILE=<file> "
"or provide a path to a valid emscripten installation via the EMSDK "
"environment variable.")
endfunction()
function(__qt_internal_get_qt_build_emsdk_version out_var)
if(QT6_INSTALL_PREFIX)
set(WASM_BUILD_DIR "${QT6_INSTALL_PREFIX}")
elseif(QT_BUILD_DIR)
set(WASM_BUILD_DIR "${QT_BUILD_DIR}")
endif()
if(EXISTS "${WASM_BUILD_DIR}/src/corelib/global/qconfig.h")
file(READ "${WASM_BUILD_DIR}/src/corelib/global/qconfig.h" ver)
elseif(EXISTS "${WASM_BUILD_DIR}/include/QtCore/qconfig.h")
file(READ "${WASM_BUILD_DIR}/include/QtCore/qconfig.h" ver)
endif()
if (ver)
string(REGEX MATCH "#define QT_EMCC_VERSION.\"[0-9]+\\.[0-9]+\\.[0-9]+\"" emOutput ${ver})
string(REGEX MATCH "[0-9]+\\.[0-9]+\\.[0-9]+" build_emcc_version "${emOutput}")
set(${out_var} "${build_emcc_version}" PARENT_SCOPE)
endif()
endfunction()
function(_qt_test_emscripten_version)
__qt_internal_get_emcc_recommended_version(_recommended_emver)
__qt_internal_get_emroot_path_suffix_from_emsdk_env(emroot_path)
__qt_internal_query_emsdk_version("${emroot_path}" TRUE current_emsdk_ver)
__qt_internal_get_qt_build_emsdk_version(qt_build_emcc_version)
if(NOT "${qt_build_emcc_version}" STREQUAL "" AND NOT "${qt_build_emcc_version}" STREQUAL "${current_emsdk_ver}")
message("Qt Wasm built with Emscripten version: ${qt_build_emcc_version}")
message("You are using Emscripten version: ${current_emsdk_ver}")
message("The recommended version of Emscripten for this Qt is: ${_recommended_emver}")
message("This may not work correctly")
endif()
endfunction()