[libc++][test] Makes pthread a flag.

[Mordante]

Summary

Using pthread may affect the compilation too not only the linking.
Therefore pthread is changed from a link flag to a generic flag used for
both compilation and linking.

This fixes an issue when using modules since the use of the pthread flag
makes the BMI files not compatible.

[Mordante]

CI fixes.

[Mordante]

CI fixes.

libcxx/test/configs/ibm-libc++-shared.cfg.in

 # This testing configuration handles running the test suite against libc++ on
 # AIX using a shared library.
 #
 
 lit_config.load_config(config, '@CMAKE_CURRENT_BINARY_DIR@/cmake-bridge.cfg')
 
-config.substitutions.append(('%{flags}', ''))
+config.substitutions.append(('%{flags}', '-pthread'))
 config.substitutions.append(('%{compile_flags}',
-    '-nostdinc++ -D__LIBC_NO_CPP_MATH_OVERLOADS__ -I %{include} -I %{libcxx}/test/support -pthread'
+    '-nostdinc++ -D__LIBC_NO_CPP_MATH_OVERLOADS__ -I %{include} -I %{libcxx}/test/support'
 ))
 config.substitutions.append(('%{link_flags}',
     '-nostdlib++ -L %{lib} -lc++ -lc++abi -latomic -Wl,-bbigtoc'
 ))
 config.substitutions.append(('%{exec}',
     '%{executor} --execdir %T --env LIBPATH=%{lib} -- '
 ))
 

libcxx/test/configs/llvm-libc++-shared-gcc.cfg.in

 # This testing configuration handles running the test suite against LLVM's libc++
 # using a shared library, with GCC. This is done differently from Clang because
 # GCC does not support the -nostdlib++ command-line flag.
 
 lit_config.load_config(config, '@CMAKE_CURRENT_BINARY_DIR@/cmake-bridge.cfg')
 
-config.substitutions.append(('%{flags}', ''))
+config.substitutions.append(('%{flags}', '-pthread'))
 config.substitutions.append(('%{compile_flags}',
     '-nostdinc++ -I %{include} -I %{target-include} -I %{libcxx}/test/support'
 ))
 config.substitutions.append(('%{link_flags}',
-    '-L %{lib} -Wl,-rpath,%{lib} -nodefaultlibs -lc++ -lm -lgcc_s -lgcc -lpthread -lc -lgcc_s -lgcc -latomic'
+    '-L %{lib} -Wl,-rpath,%{lib} -nodefaultlibs -lc++ -lm -lgcc_s -lgcc -lc -lgcc_s -lgcc -latomic'
 ))
 config.substitutions.append(('%{exec}',
     '%{executor} --execdir %T -- '
 ))
 
 import os, site
 site.addsitedir(os.path.join('@LIBCXX_SOURCE_DIR@', 'utils'))
 import libcxx.test.params, libcxx.test.config
 libcxx.test.config.configure(
     libcxx.test.params.DEFAULT_PARAMETERS,
     libcxx.test.features.DEFAULT_FEATURES,
     config,
     lit_config
 )

libcxx/test/configs/llvm-libc++-shared.cfg.in

 # This testing configuration handles running the test suite against LLVM's libc++
 # using a shared library.
 
 lit_config.load_config(config, '@CMAKE_CURRENT_BINARY_DIR@/cmake-bridge.cfg')
 
 config.substitutions.append(('%{flags}',
-    '-isysroot {}'.format('@CMAKE_OSX_SYSROOT@') if '@CMAKE_OSX_SYSROOT@' else ''
+    '-pthread' + (' -isysroot {}'.format('@CMAKE_OSX_SYSROOT@') if '@CMAKE_OSX_SYSROOT@' else '')
 ))
 config.substitutions.append(('%{compile_flags}',
     '-nostdinc++ -I %{include} -I %{target-include} -I %{libcxx}/test/support'
 ))
 config.substitutions.append(('%{link_flags}',
-    '-nostdlib++ -L %{lib} -Wl,-rpath,%{lib} -lc++ -pthread'
+    '-nostdlib++ -L %{lib} -Wl,-rpath,%{lib} -lc++'
 ))
 config.substitutions.append(('%{exec}',
     '%{executor} --execdir %T -- '
 ))
 
 import os, site
 site.addsitedir(os.path.join('@LIBCXX_SOURCE_DIR@', 'utils'))
 import libcxx.test.params, libcxx.test.config
 libcxx.test.config.configure(
     libcxx.test.params.DEFAULT_PARAMETERS,
     libcxx.test.features.DEFAULT_FEATURES,
     config,
     lit_config
 )

libcxx/test/configs/llvm-libc++-static.cfg.in

 # This testing configuration handles running the test suite against LLVM's libc++
 # using a static library.
 
 lit_config.load_config(config, '@CMAKE_CURRENT_BINARY_DIR@/cmake-bridge.cfg')
 
 config.substitutions.append(('%{flags}',
-    '-isysroot {}'.format('@CMAKE_OSX_SYSROOT@') if '@CMAKE_OSX_SYSROOT@' else ''
+    '-pthread' + (' -isysroot {}'.format('@CMAKE_OSX_SYSROOT@') if '@CMAKE_OSX_SYSROOT@' else '')
 ))
 config.substitutions.append(('%{compile_flags}',
     '-nostdinc++ -I %{include} -I %{target-include} -I %{libcxx}/test/support'
 ))
 config.substitutions.append(('%{link_flags}',
-    '-nostdlib++ -L %{lib} -lc++ -lc++abi -pthread'
+    '-nostdlib++ -L %{lib} -lc++ -lc++abi'
 ))
 config.substitutions.append(('%{exec}',
     '%{executor} --execdir %T -- '
 ))
 
 import os, site
 site.addsitedir(os.path.join('@LIBCXX_SOURCE_DIR@', 'utils'))
 import libcxx.test.params, libcxx.test.config
 libcxx.test.config.configure(
     libcxx.test.params.DEFAULT_PARAMETERS,
     libcxx.test.features.DEFAULT_FEATURES,
     config,
     lit_config
 )