message: Build integration test with the same compiler
  Fix
diff: @@ -77,18 +77,30 @@ externalproject_add(inttest_bin
  BINARY_DIR "${CMAKE_CURRENT_BINARY_DIR}/integration"
  INSTALL_COMMAND ""
  CMAKE_CACHE_ARGS
  - # Note the space in the end: protect from CXXFLAGS env var, but
  - # still support custom flags
  + # Note the space in the end: protect from CXXFLAGS env var (see comment
  + # above), but still support custom flags
  "-DCMAKE_CXX_FLAGS:string=${INTEGRATION_TEST_CXX_FLAGS} "
  + # Build integration test with the correct compiler.
  + # https://bugs.gentoo.org/699258
  + # CMAKE_CXX_COMPILER is passed for the case if the main cmake was called
  + # with -DCMAKE_CXX_COMPILER but without -DCMAKE_TOOLCHAIN_FILE.
  + "-DCMAKE_TOOLCHAIN_FILE:path=${CMAKE_TOOLCHAIN_FILE}"
  + "-DCMAKE_CXX_COMPILER=${CMAKE_CXX_COMPILER}"
  +
  "-DGTEST_ROOT:path=${GTEST_ROOT}"
  "-DGMOCK_ROOT:path=${GMOCK_ROOT}"
  "-DZNC_BIN_DIR:path=${CMAKE_INSTALL_FULL_BINDIR}"
  "-DQt5_HINTS:path=${brew_qt5}")
  add_custom_target(inttest COMMAND
  + # MAKEFLAGS:
  # Prevent a warning from test of znc-buildmod, when inner make
  # discovers that there is an outer make and tries to use it:
  # gmake[4]: warning: jobserver unavailable: using -j1. Add '+' to parent make rule.
  # This option doesn't affect ninja, which doesn't show that warning anyway.
  - ${CMAKE_COMMAND} -E env MAKEFLAGS=
  + #
  + # CXX:
  + # znc-buildmod should use the correct compiler.
  + # https://bugs.gentoo.org/699258 is an example of how it can go wrong.
  + ${CMAKE_COMMAND} -E env MAKEFLAGS= CXX=${CMAKE_CXX_COMPILER}
  "${CMAKE_CURRENT_BINARY_DIR}/integration/inttest")
  add_dependencies(inttest inttest_bin)
  