Do not link private dependent shared libraries on OS X > 10.4

The default OS X 10.4 linker incorrectly searches for dependencies of
linked shared libraries only under the -isysroot location.  It fails to
find dependencies of linked shared libraries in cases such as the
ExportImport test.  It produces errors like:

 /usr/libexec/gcc/i686-apple-darwin8/4.0.1/ld: warning can't open dynamic library:
 libtestLib3Imp.dylib
 referenced from: /.../ExportImport/Root/lib/libtestLib3lib.1.2.dylib
 (checking for undefined symbols may be affected) (No such file or directory, errno = 2)
 /usr/libexec/gcc/i686-apple-darwin8/4.0.1/ld: Undefined symbols: _testLib3Imp
 referenced from libtestLib3lib expected to be defined in
 libtestLib3Imp.dylib

or with CMAKE_SKIP_RPATH off to enable install_name in the Export side:

 /usr/libexec/gcc/i686-apple-darwin8/4.0.1/ld: warning can't open dynamic library:
 /Developer/SDKs/MacOSX10.4u.sdk/.../ExportImport/Export/impl/libtestLib3Imp.dylib
 referenced from: /.../ExportImport/Export/libtestLib3lib.1.2.dylib
 (checking for undefined symbols may be affected) (No such file or directory, errno = 2)
 /usr/libexec/gcc/i686-apple-darwin8/4.0.1/ld: Undefined symbols:_testLib3Imp
 referenced from libtestLib3lib expected to be defined in
 /.../ExportImport/Export/impl/libtestLib3Imp.dylib

Note how "/Developer/SDKs/MacOSX10.4u.sdk" is prepended to the dependent
library path.

Commit 2cff26fa (Support linking to shared libs with dependent libs,
2008-01-31) and commit 82fcaebe (Pass dependent library search path to
linker on some platforms, 2008-02-01) worked around the problem by
defining platform variable CMAKE_LINK_DEPENDENT_LIBRARY_FILES.  It tells
CMake to link to dependent libraries explicitly by their path thus
telling the linker where to find them.

Unfortunately the workaround had the side effect of linking dependent
libraries and defeats most benefits of LINK_INTERFACE_LIBRARIES.
Fortunately OS X 10.5 and above do not need to find transitive
dependencies at all so we can avoid the workaround on Modern OS X.
This commit is contained in:
Brad King 2011-12-14 13:59:39 -05:00
parent 183b95098e
commit 5d9934312d
2 changed files with 10 additions and 6 deletions

View File

@ -187,11 +187,13 @@ IF(XCODE)
SET(CMAKE_INCLUDE_SYSTEM_FLAG_CXX)
ENDIF(XCODE)
# Need to list dependent shared libraries on link line. When building
# with -isysroot (for universal binaries), the linker always looks for
# dependent libraries under the sysroot. Listing them on the link
# line works around the problem.
SET(CMAKE_LINK_DEPENDENT_LIBRARY_FILES 1)
IF("${_CURRENT_OSX_VERSION}" VERSION_LESS "10.5")
# Need to list dependent shared libraries on link line. When building
# with -isysroot (for universal binaries), the linker always looks for
# dependent libraries under the sysroot. Listing them on the link
# line works around the problem.
SET(CMAKE_LINK_DEPENDENT_LIBRARY_FILES 1)
ENDIF()
SET(CMAKE_C_CREATE_SHARED_LIBRARY_FORBIDDEN_FLAGS -w)
SET(CMAKE_CXX_CREATE_SHARED_LIBRARY_FORBIDDEN_FLAGS -w)

View File

@ -161,7 +161,9 @@ listed on the command line.
- On Windows, DLLs are not directly linked, and the import libraries
have no transitive dependencies.
- On Mac, we need to actually list the transitive dependencies.
- On Mac OS X 10.5 and above transitive dependencies are not needed.
- On Mac OS X 10.4 and below we need to actually list the dependencies.
Otherwise when using -isysroot for universal binaries it cannot
find the dependent libraries. Listing them on the command line
tells the linker where to find them, but unfortunately also links