[libcxx] r283659 - [cmake] Split linked libraries into private & public, for linker script
Hal Finkel via cfe-commits
cfe-commits at lists.llvm.org
Sat Oct 8 19:43:02 PDT 2016
----- Original Message -----
> From: "Hal Finkel" <hfinkel at anl.gov>
> To: "Hal Finkel" <hfinkel at anl.gov>
> Cc: cfe-commits at lists.llvm.org, "Michal Gorny" <mgorny at gentoo.org>
> Sent: Saturday, October 8, 2016 9:34:58 PM
> Subject: Re: [libcxx] r283659 - [cmake] Split linked libraries into private & public, for linker script
>
> ----- Original Message -----
> > From: "Hal Finkel via cfe-commits" <cfe-commits at lists.llvm.org>
> > To: "Michal Gorny" <mgorny at gentoo.org>
> > Cc: cfe-commits at lists.llvm.org
> > Sent: Saturday, October 8, 2016 6:37:50 PM
> > Subject: Re: [libcxx] r283659 - [cmake] Split linked libraries into
> > private & public, for linker script
> >
> > Hi Michal,
> >
> > All of the libc++ and libc++abi regression tests are now failing on
> > my Linux build system with this error:
> >
> > /usr/bin/ld: cannot find -lcxxabi_shared
>
> Alright, the problem here is that you've assumed, by doing this:
>
> > > ${LIBCXX_SOURCE_DIR}/utils/gen_link_script/gen_link_script.py
> > > ARGS
> > > "$<TARGET_LINKER_FILE:cxx_shared>"
> > > - "${SCRIPT_ABI_LIBNAME}"
> > > + "\"${LIBCXX_LIBRARIES_PUBLIC}\""
Ah, I see. The code right about this used to handle this situation:
# Get the name of the ABI library and handle the case where CXXABI_LIBNAME
# is a target name and not a library. Ex cxxabi_shared.
set(SCRIPT_ABI_LIBNAME "${LIBCXX_CXX_ABI_LIBRARY}")
if (SCRIPT_ABI_LIBNAME STREQUAL "cxxabi_shared")
set(SCRIPT_ABI_LIBNAME "c++abi")
endif()
and now it doesn't because you no longer use SCRIPT_ABI_LIBNAME as the argument to gen_link_script.py. Let me see if I can fix this...
-Hal
>
> that all of the items in the LIBCXX_LIBRARIES_PUBLIC list are actual
> library names. They might not be, but rather, they might be CMake
> targets instead:
>
> elseif ("${LIBCXX_CXX_ABI_LIBNAME}" STREQUAL "libcxxabi")
> if (LIBCXX_CXX_ABI_INTREE)
> # Link against just-built "cxxabi" target.
> if (LIBCXX_ENABLE_STATIC_ABI_LIBRARY)
> set(CXXABI_LIBNAME cxxabi_static)
> else()
> set(CXXABI_LIBNAME cxxabi_shared)
> endif()
> set(LIBCXX_LIBCPPABI_VERSION "2" PARENT_SCOPE)
> else()
> # Assume c++abi is installed in the system, rely on -lc++abi link
> flag.
> set(CXXABI_LIBNAME "c++abi")
> endif()
>
> So we might have cxxabi_static or cxxabi_shared in the list.
>
> -Hal
>
> >
> > My build directory has only these:
> >
> > lib/libc++.a
> > lib/libc++abi.so
> > lib/libc++abi.so.1
> > lib/libc++abi.so.1.0
> > lib/libc++experimental.a
> > lib/libc++.so
> > lib/libc++.so.1
> > lib/libc++.so.1.0
> >
> > -Hal
> >
> > ----- Original Message -----
> > > From: "Michal Gorny via cfe-commits" <cfe-commits at lists.llvm.org>
> > > To: cfe-commits at lists.llvm.org
> > > Sent: Saturday, October 8, 2016 5:27:46 AM
> > > Subject: [libcxx] r283659 - [cmake] Split linked libraries into
> > > private & public, for linker script
> > >
> > > Author: mgorny
> > > Date: Sat Oct 8 05:27:45 2016
> > > New Revision: 283659
> > >
> > > URL: http://llvm.org/viewvc/llvm-project?rev=283659&view=rev
> > > Log:
> > > [cmake] Split linked libraries into private & public, for linker
> > > script
> > >
> > > Introduce LIBCXX_LIBRARIES_PUBLIC in addition to LIBCXX_LIBRARIES
> > > that
> > > holds 'public' interface libraries -- that is, libraries that
> > > both
> > > libc++ links to and programs linked against it need to link to.
> > >
> > > Currently this includes the ABI library and optionally -lunwind
> > > (when
> > > LIBCXXABI_USE_LLVM_UNWINDER is on). The libraries are included in
> > > the
> > > linker script, in order to make it possible to link C++ programs
> > > using
> > > clang with compiler-rt runtime out-of-the-box.
> > >
> > > Differential Revision: https://reviews.llvm.org/D25008
> > >
> > > Modified:
> > > libcxx/trunk/CMakeLists.txt
> > > libcxx/trunk/lib/CMakeLists.txt
> > > libcxx/trunk/utils/gen_link_script/gen_link_script.py
> > >
> > > Modified: libcxx/trunk/CMakeLists.txt
> > > URL:
> > > http://llvm.org/viewvc/llvm-project/libcxx/trunk/CMakeLists.txt?rev=283659&r1=283658&r2=283659&view=diff
> > > ==============================================================================
> > > --- libcxx/trunk/CMakeLists.txt (original)
> > > +++ libcxx/trunk/CMakeLists.txt Sat Oct 8 05:27:45 2016
> > > @@ -270,9 +270,13 @@ set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${LIB
> > > # LIBCXX_CXX_FLAGS: General flags for both the compiler and
> > > linker.
> > > # LIBCXX_COMPILE_FLAGS: Compile only flags.
> > > # LIBCXX_LINK_FLAGS: Linker only flags.
> > > +# LIBCXX_LIBRARIES: Private libraries libc++ is linked to.
> > > +# LIBCXX_LIBRARIES_PUBLIC: Public libraries libc++ is linked to,
> > > +# also exposed in the linker script.
> > > set(LIBCXX_COMPILE_FLAGS "")
> > > set(LIBCXX_LINK_FLAGS "")
> > > set(LIBCXX_LIBRARIES "")
> > > +set(LIBCXX_LIBRARIES_PUBLIC "")
> > >
> > > # Include macros for adding and removing libc++ flags.
> > > include(HandleLibcxxFlags)
> > >
> > > Modified: libcxx/trunk/lib/CMakeLists.txt
> > > URL:
> > > http://llvm.org/viewvc/llvm-project/libcxx/trunk/lib/CMakeLists.txt?rev=283659&r1=283658&r2=283659&view=diff
> > > ==============================================================================
> > > --- libcxx/trunk/lib/CMakeLists.txt (original)
> > > +++ libcxx/trunk/lib/CMakeLists.txt Sat Oct 8 05:27:45 2016
> > > @@ -33,9 +33,17 @@ add_link_flags_if(LIBCXX_CXX_ABI_LIBRARY
> > >
> > > add_library_flags_if(LIBCXX_COVERAGE_LIBRARY
> > > "${LIBCXX_COVERAGE_LIBRARY}")
> > >
> > > -add_library_flags_if(LIBCXX_ENABLE_STATIC_ABI_LIBRARY
> > > "-Wl,--whole-archive" "-Wl,-Bstatic")
> > > -add_library_flags("${LIBCXX_CXX_ABI_LIBRARY}")
> > > -add_library_flags_if(LIBCXX_ENABLE_STATIC_ABI_LIBRARY
> > > "-Wl,-Bdynamic" "-Wl,--no-whole-archive")
> > > +if (LIBCXX_ENABLE_STATIC_ABI_LIBRARY)
> > > + add_library_flags("-Wl,--whole-archive" "-Wl,-Bstatic")
> > > + add_library_flags("${LIBCXX_CXX_ABI_LIBRARY}")
> > > + add_library_flags("-Wl,-Bdynamic" "-Wl,--no-whole-archive")
> > > +elseif (APPLE AND (LIBCXX_CXX_ABI_LIBNAME STREQUAL "libcxxabi"
> > > OR
> > > + LIBCXX_CXX_ABI_LIBNAME STREQUAL "none"))
> > > + # Apple re-exports libc++abi in libc++, so don't make it
> > > public
> > > + add_library_flags("${LIBCXX_CXX_ABI_LIBRARY}")
> > > +else()
> > > + list(APPEND LIBCXX_LIBRARIES_PUBLIC
> > > "${LIBCXX_CXX_ABI_LIBRARY}")
> > > +endif()
> > >
> > > if (APPLE AND LLVM_USE_SANITIZER)
> > > if (("${LLVM_USE_SANITIZER}" STREQUAL "Address") OR
> > > @@ -67,7 +75,7 @@ if (APPLE AND LLVM_USE_SANITIZER)
> > > endif()
> > > endif()
> > >
> > > -# Generate library list.
> > > +# Generate private library list.
> > > add_library_flags_if(LIBCXX_HAS_PTHREAD_LIB pthread)
> > > add_library_flags_if(LIBCXX_HAS_C_LIB c)
> > > add_library_flags_if(LIBCXX_HAS_M_LIB m)
> > > @@ -75,6 +83,11 @@ add_library_flags_if(LIBCXX_HAS_RT_LIB r
> > > add_library_flags_if(LIBCXX_HAS_GCC_S_LIB gcc_s)
> > > add_library_flags_if(LIBCXX_HAVE_CXX_ATOMICS_WITH_LIB atomic)
> > >
> > > +# Add the unwinder library.
> > > +if (LIBCXXABI_USE_LLVM_UNWINDER)
> > > + list(APPEND LIBCXX_LIBRARIES_PUBLIC unwind)
> > > +endif()
> > > +
> > > # Setup flags.
> > > if (NOT WIN32)
> > > add_flags_if_supported(-fPIC)
> > > @@ -151,7 +164,9 @@ set(LIBCXX_TARGETS)
> > > # Build the shared library.
> > > if (LIBCXX_ENABLE_SHARED)
> > > add_library(cxx_shared SHARED $<TARGET_OBJECTS:cxx_objects>)
> > > - target_link_libraries(cxx_shared ${LIBCXX_LIBRARIES})
> > > + target_link_libraries(cxx_shared
> > > + PRIVATE ${LIBCXX_LIBRARIES}
> > > + PUBLIC ${LIBCXX_LIBRARIES_PUBLIC})
> > > set_target_properties(cxx_shared
> > > PROPERTIES
> > > LINK_FLAGS "${LIBCXX_LINK_FLAGS}"
> > > @@ -165,7 +180,9 @@ endif()
> > > # Build the static library.
> > > if (LIBCXX_ENABLE_STATIC)
> > > add_library(cxx_static STATIC $<TARGET_OBJECTS:cxx_objects>)
> > > - target_link_libraries(cxx_static ${LIBCXX_LIBRARIES})
> > > + target_link_libraries(cxx_static
> > > + PRIVATE ${LIBCXX_LIBRARIES}
> > > + PUBLIC ${LIBCXX_LIBRARIES_PUBLIC})
> > > set_target_properties(cxx_static
> > > PROPERTIES
> > > LINK_FLAGS "${LIBCXX_LINK_FLAGS}"
> > > @@ -238,7 +255,7 @@ if (LIBCXX_ENABLE_SHARED AND LIBCXX_ENAB
> > > ${PYTHON_EXECUTABLE}
> > > ${LIBCXX_SOURCE_DIR}/utils/gen_link_script/gen_link_script.py
> > > ARGS
> > > "$<TARGET_LINKER_FILE:cxx_shared>"
> > > - "${SCRIPT_ABI_LIBNAME}"
> > > + "\"${LIBCXX_LIBRARIES_PUBLIC}\""
> > > WORKING_DIRECTORY ${LIBCXX_BUILD_DIR}
> > > )
> > > endif()
> > >
> > > Modified: libcxx/trunk/utils/gen_link_script/gen_link_script.py
> > > URL:
> > > http://llvm.org/viewvc/llvm-project/libcxx/trunk/utils/gen_link_script/gen_link_script.py?rev=283659&r1=283658&r2=283659&view=diff
> > > ==============================================================================
> > > --- libcxx/trunk/utils/gen_link_script/gen_link_script.py
> > > (original)
> > > +++ libcxx/trunk/utils/gen_link_script/gen_link_script.py Sat Oct
> > > 8
> > > 05:27:45 2016
> > > @@ -22,7 +22,7 @@ def help_and_exit():
> > > help_msg = \
> > > """Usage
> > >
> > > - gen_link_script.py [--help] [--dryrun] <path/to/libcxx.so>
> > > <abi_libname>
> > > + gen_link_script.py [--help] [--dryrun] <path/to/libcxx.so>
> > > <public_libs>
> > >
> > > Generate a linker script that links libc++ to the proper ABI
> > > library.
> > > The script replaces the specified libc++ symlink.
> > > @@ -31,8 +31,7 @@ def help_and_exit():
> > > Arguments
> > > <path/to/libcxx.so> - The top level symlink to the versioned
> > > libc++ shared
> > > library. This file is replaced with a
> > > linker
> > > script.
> > > - <abi_libname> - The name of the ABI library to use in
> > > the
> > > linker script.
> > > - The name must be one of [c++abi, stdc++,
> > > supc++, cxxrt].
> > > + <public_libs> - List of library names to include in
> > > linker
> > > script.
> > >
> > > Exit Status:
> > > 0 if OK,
> > > @@ -53,11 +52,11 @@ def parse_args():
> > > if len(args) != 2:
> > > usage_and_exit()
> > > symlink_file = args[0]
> > > - abi_libname = args[1]
> > > - return dryrun, symlink_file, abi_libname
> > > + public_libs = args[1].split(';')
> > > + return dryrun, symlink_file, public_libs
> > >
> > > def main():
> > > - dryrun, symlink_file, abi_libname = parse_args()
> > > + dryrun, symlink_file, public_libs = parse_args()
> > >
> > > # Check that the given libc++.so file is a valid symlink.
> > > if not os.path.islink(symlink_file):
> > > @@ -66,15 +65,12 @@ def main():
> > > # Read the symlink so we know what libc++ to link to in the
> > > linker script.
> > > linked_libcxx = os.readlink(symlink_file)
> > >
> > > - # Check that the abi_libname is one of the supported values.
> > > - supported_abi_list = ['c++abi', 'stdc++', 'supc++', 'cxxrt']
> > > - if abi_libname not in supported_abi_list:
> > > - print_and_exit("abi name '%s' is not supported: Use one
> > > of
> > > %r" %
> > > - (abi_libname, supported_abi_list))
> > > + # Prepare the list of public libraries to link.
> > > + public_libs = ['-l%s' % l for l in public_libs]
> > >
> > > # Generate the linker script contents and print the script
> > > and
> > > destination
> > > # information.
> > > - contents = "INPUT(%s -l%s)" % (linked_libcxx, abi_libname)
> > > + contents = "INPUT(%s %s)" % (linked_libcxx, '
> > > '.join(public_libs))
> > > print("GENERATING SCRIPT: '%s' as file %s" % (contents,
> > > symlink_file))
> > >
> > > # Remove the existing libc++ symlink and replace it with the
> > > script.
> > >
> > >
> > > _______________________________________________
> > > cfe-commits mailing list
> > > cfe-commits at lists.llvm.org
> > > http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
> > >
> >
> > --
> > Hal Finkel
> > Lead, Compiler Technology and Programming Languages
> > Leadership Computing Facility
> > Argonne National Laboratory
> > _______________________________________________
> > cfe-commits mailing list
> > cfe-commits at lists.llvm.org
> > http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
> >
>
> --
> Hal Finkel
> Lead, Compiler Technology and Programming Languages
> Leadership Computing Facility
> Argonne National Laboratory
>
--
Hal Finkel
Lead, Compiler Technology and Programming Languages
Leadership Computing Facility
Argonne National Laboratory
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