Some compilers use implicit link options of the form
-lcrt*.o
-lgcc*
-lSystem (on Mac)
-lSystemStubs (on Mac)
that provide system-wide symbols not specific to any language.
These need not be listed explicitly for mixed-language linking.
We teach CMake to remove the above items from the implicit library list
of each language. This change makes it possible to mix GNU compiler
versions in some cases.
The regex used by CMAKE_PARSE_IMPLICIT_LINK_INFO to detect link lines
should not match lines that happen to have ".../ld.../..." in them. A
linker name should match only as the last component of a path.
See issue #9666.
This commit teaches the CMAKE_PARSE_IMPLICIT_LINK_INFO function to log
its actions. We store the log in CMakeFiles/CMakeOutput.log at the top
of the project build tree. This will make diagnosis of implicit link
information parsing problems easier.
This adds sample linker invocation lines for the Intel compiler on
Linux. In particular, this exercises the case when "ld" appears without
a full path.
The Sun Fortran compiler passes -zallextract and -zdefaultextract to the
linker so that all objects from one of its archives are included in the
link. This teaches the implicit options parser to recognize the flags.
We need to pass them explicitly on C++ link lines when Fortran code is
linked.
The commit "Avoid case change in ImplicitLinkInfo test" did not change
all of the paths to mingw, so some case change still occurs. This
changes more of them.
Since "get_filename_component(... ABSOLUTE)" retrieves the actual case
for existing paths on windows, we need to use an obscure path for mingw.
Otherwise the test can fail just because the case of the paths changes.
This tests the internal CMakeParseImplicitLinkInfo.cmake module to
ensure that implicit link information is extracted correctly. The test
contains many manually verified examples from a variety of systems.
Brad King