Faster LLVM debug builds. Used primarily during dev.

fast.cmake

cmake_minimum_required(VERSION 3.4)

execute_process(
    COMMAND "grep" "^processor" "/proc/cpuinfo"
    COMMAND "wc" "-l"
    COMMAND "tr" "-d" "'\n'"
    OUTPUT_VARIABLE ncpu
)

set(GIT_ORIGIN "file://$ENV{HOME}/usr/git" CACHE STRING "")

message("Building with ${ncpu} cpus")
set(LLVM_PARALLEL_COMPILE_JOBS ${ncpu} CACHE STRING "")
set(LLVM_PARALLEL_LINK_JOBS ${ncpu} CACHE STRING "")

set(BUILD_SHARED_LIBS ON CACHE BOOL "")
set(CMAKE_C_COMPILER "clang" CACHE PATH "")
set(CMAKE_CXX_COMPILER "clang++" CACHE PATH "")

set(LLVM_ENABLE_LLD ON CACHE PATH "")

set(CMAKE_BUILD_TYPE "Debug" CACHE STRING "")
set(CMAKE_C_FLAGS "-O0" CACHE STRING "")
set(CMAKE_CXX_FLAGS "-O0" CACHE STRING "")
set(CMAKE_INSTALL_PREFIX "$ENV{HOME}/usr" CACHE PATH "")
set(LLVM_TARGETS_TO_BUILD "X86" CACHE STRING "")
set(LLVM_BUILD_RUNTIME OFF CACHE BOOL "")
set(LLVM_ENABLE_ASSERTIONS ON CACHE BOOL "")
# set(LLVM_USE_SANITIZER "MemoryWithOrigins" CACHE STRING "")

# ignore tools/clang
set(LLVM_TOOL_CLANG_BUILD OFF CACHE BOOL "")