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This commit is contained in:
Alexey Milovidov 2019-01-20 01:08:40 +03:00
parent 2996d70c97
commit 203de2aa02
1 changed files with 21 additions and 1 deletions
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22
CMakeLists.txt
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@ -157,13 +157,27 @@ set (CMAKE_C_FLAGS_DEBUG "${CMAKE_C_FLAGS_DEBUG} -O0 -g3 -ggdb3
include (cmake/use_libcxx.cmake)
# Set standard, system and compiler libraries explicitly.
# This is intended for more control of what we are linking.
set (DEFAULT_LIBS "")
if (OS_LINUX AND NOT UNBUNDLED)
# Note: this probably has no effict, but I'm not an expert in CMake.
set (CMAKE_C_IMPLICIT_LINK_LIBRARIES "")
set (CMAKE_CXX_IMPLICIT_LINK_LIBRARIES "")
# Disable default linked libraries.
set (DEFAULT_LIBS "-nodefaultlibs")
# Add C++ libraries.
#
# This consist of:
# - C++ standard library (like implementation of std::string);
# - C++ ABI implementation (functions for exceptions like __cxa_throw, RTTI, etc);
# - functions for internal implementation of exception handling (stack unwinding based on DWARF info; TODO replace with bundled libunwind);
# - compiler builtins (example: functions for implementation of __int128 operations);
#
# There are two variants of C++ library: libc++ (from LLVM compiler infrastructure) and libstdc++ (from GCC).
if (USE_LIBCXX)
set (BUILTINS_LIB_PATH "")
if (COMPILER_CLANG)
@ -175,13 +189,19 @@ if (OS_LINUX AND NOT UNBUNDLED)
set (DEFAULT_LIBS "${DEFAULT_LIBS} -Wl,-Bstatic -lstdc++ -lgcc_eh -lgcc -Wl,-Bdynamic")
endif ()
# Linking with GLIBC prevents portability of binaries to older systems.
# We overcome this behaviour by statically linking with our own implementation of all new symbols (that don't exist in older Libc or have infamous "symbol versioning").
# The order of linking is important: 'glibc-compatibility' must be before libc but after all other libraries.
if (GLIBC_COMPATIBILITY)
message (STATUS "Some symbols from glibc will be replaced for compatibility")
set (DEFAULT_LIBS "${DEFAULT_LIBS} -Wl,-Bstatic libs/libglibc-compatibility/libglibc-compatibility.a -Wl,-Bdynamic")
set (DEFAULT_LIBS "${DEFAULT_LIBS} libs/libglibc-compatibility/libglibc-compatibility.a")
endif ()
# Add Libc. GLIBC is actually a collection of interdependent libraries.
set (DEFAULT_LIBS "${DEFAULT_LIBS} -lrt -ldl -lpthread -lm -lc")
# Note: we'd rather use Musl libc library, but it's little bit more difficult to use.
message(STATUS "Default libraries: ${DEFAULT_LIBS}")
endif ()