Merge 'cmake: sync with configure.py (10/n)' from Kefu Chai

- build: cmake: use different names for output of check_cxx_compiler_flag
- build: cmake: only add supported warning flags to CMAKE_CXX_FLAGS
- build: cmake: limit the number of link job

Closes #13098

* github.com:scylladb/scylladb:
  build: cmake: limit the number of link job
  build: cmake: only add supported warning flags to CMAKE_CXX_FLAGS
  build: cmake: use different names for output of check_cxx_compiler_flag

CMakeLists.txt

@@ -19,6 +19,7 @@ include("mode.${build_mode}")
 add_compile_definitions(
     ${Seastar_DEFINITIONS_${build_mode}}
     FMT_DEPRECATED_OSTREAM)
+include("limit_jobs")
 # Configure Seastar compile options to align with Scylla
 set(CMAKE_CXX_STANDARD "20" CACHE INTERNAL "")
 set(CMAKE_CXX_EXTENSIONS ON CACHE INTERNAL "")

cmake/limit_jobs.cmake

@@ -0,0 +1,16 @@
+set(Seastar_LINK_MEM_PER_JOB 1024 CACHE INTERNAL "Maximum memory used by each link job in (in MiB)")
+
+cmake_host_system_information(
+  RESULT _total_mem
+  QUERY AVAILABLE_PHYSICAL_MEMORY)
+math(EXPR _link_pool_depth "${_total_mem} / ${Seastar_LINK_MEM_PER_JOB}")
+if(_link_pool_depth EQUAL 0)
+  set(_link_pool_depth 1)
+endif()
+set_property(
+  GLOBAL
+  APPEND
+  PROPERTY JOB_POOLS
+    link_pool=${_link_pool_depth}
+    submodule_pool=1)
+set(CMAKE_JOB_POOL_LINK link_pool)

cmake/mode.common.cmake

@@ -6,14 +6,14 @@ set(disabled_warnings
   parentheses-equality
   unsupported-friend)
 include(CheckCXXCompilerFlag)
-foreach(warning disabled_warnings)
-  check_cxx_compiler_flag("-Wno-${warning}" _warning_supported)
-  if(_warning_supported)
+foreach(warning ${disabled_warnings})
+  check_cxx_compiler_flag("-Wno-${warning}" _warning_supported_${warning})
+  if(_warning_supported_${warning})
     list(APPEND _supported_warnings ${warning})
   endif()
 endforeach()
-list(TRANSFORM disabled_warnings PREPEND "-Wno-")
-string(JOIN " " CMAKE_CXX_FLAGS "-Wall" "-Werror" ${disabled_warnings})
+list(TRANSFORM _supported_warnings PREPEND "-Wno-")
+string(JOIN " " CMAKE_CXX_FLAGS "-Wall" "-Werror" ${_supported_warnings})
 
 function(default_target_arch arch)
   set(x86_instruction_sets i386 i686 x86_64)