Don't add unnecessary compiler flags to llvm-config output
Summary:
llvm-config --cxxflags --cflags, should only output the minimal flags
required to link against the llvm libraries. They currently contain
all flags used to compile llvm including flags like -g, -pedantic,
-Wall, etc, which users may not always want.
This changes the llvm-config output to only include flags that have been
explictly added to the COMPILE_FLAGS property of the llvm-config target
by the llvm build system.
llvm.org/PR8220
Output from llvm-config when running cmake with:
cmake -G Ninja .. -DCMAKE_CXX_FLAGS=-funroll-loops
Before:
--cppflags: -I$HEADERS_DIR/llvm/include -I$HEADERS_DIR/llvm/build/include
-D_GNU_SOURCE -D_DEBUG -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
--cflags: -I$HEADERS_DIR/llvm/include -I$HEADERS_DIR/llvm/build/include
-fPIC -Werror=date-time -Wall -Wextra -Wno-unused-parameter -Wwrite-strings \
-Wno-missing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough \
-Wno-comment -fdiagnostics-color -g -D_GNU_SOURCE -D_DEBUG -D__STDC_CONSTANT_MACROS \
-D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
--cxxflags: -I$HEADERS_DIR/llvm/include -I$HEADERS_DIR/llvm/build/include\
-funroll-loops -fPIC -fvisibility-inlines-hidden -Werror=date-time -std=c++11 -Wall \
-Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wno-missing-field-initializers \
-pedantic -Wno-long-long -Wimplicit-fallthrough -Wno-maybe-uninitialized \
-Wno-class-memaccess -Wno-noexcept-type -Wdelete-non-virtual-dtor -Wno-comment \
-fdiagnostics-color -g -fno-exceptions -fno-rtti -D_GNU_SOURCE -D_DEBUG \
-D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS"
After:
--cppflags: -I$HEADERS_DIR/llvm/include -I$HEADERS_DIR/llvm/build/include \
-D_GNU_SOURCE -D_DEBUG -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
--cflags: -I$HEADERS_DIR/llvm/include -I$HEADERS_DIR/llvm/build/include \
-D_GNU_SOURCE -D_DEBUG -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
--cxxflags: -I$HEADERS_DIR/llvm/include -I$HEADERS_DIR/llvm/build/include \
-std=c++11 -fno-exceptions -fno-rtti \
-D_GNU_SOURCE -D_DEBUG -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS
Reviewers: sylvestre.ledru, infinity0, mgorny
Reviewed By: sylvestre.ledru, mgorny
Subscribers: mgorny, dmgreen, llvm-commits
Differential Revision: https://reviews.llvm.org/D55391
llvm-svn: 349068
dda331284d