Update CMake build instructions

[wmaxey]

This includes changes reflecting that LLVM is no longer a dependency on Windows builds and how to build libcudacxx tests.

[robertmaynard]

You can drop mkdir, cd, and go with

cmake -S . -B build ....

[jrhemstad]

I can't comment on the line, but is apt-get -y install llvm needed anymore?

Yep, as stated it's still need for cmake modules :)

[jrhemstad]

re: #175 (comment) should we include -DHAVE_CXX_ATOMICS64_WITHOUT_LIB=True -DHAVE_CXX_ATOMICS_WITHOUT_LIB=True to avoid the cmake warning about libatomic?

[veictry]

variable "LIBCXX_LIT_SITE_CONFIG" in perform_tests.bash seems to need to be ${LIBCUDACXX_PATH}/libcxx/build/test/lit.site.cfg but not ${LIBCUDACXX_PATH}/libcxx/build/libcxx/test/lit.site.cfg

[wmaxey]

variable "LIBCXX_LIT_SITE_CONFIG" in perform_tests.bash seems to need to be ${LIBCUDACXX_PATH}/libcxx/build/test/lit.site.cfg but not ${LIBCUDACXX_PATH}/libcxx/build/libcxx/test/lit.site.cfg

That script should be correct. There are two separate lit configs created depending on which tests have been enabled.

LIBCXX_SITE_CONFIG and LIBCUDACXX_SITE_CONFIG.

The documentation will need to be updated to reflect that as well.

[veictry]

variable "LIBCXX_LIT_SITE_CONFIG" in perform_tests.bash seems to need to be ${LIBCUDACXX_PATH}/libcxx/build/test/lit.site.cfg but not ${LIBCUDACXX_PATH}/libcxx/build/libcxx/test/lit.site.cfg

That script should be correct. There are two separate lit configs created depending on which tests have been enabled.

LIBCXX_LIT_SITE_CONFIG and LIBCUDACXX_LIT_SITE_CONFIG.

The documentation will need to be updated to reflect that as well.

Hi Wesley,

 Yes. I tried to ENABLE_LIBCXX_TESTS and it made a build for LIBCXX part (not LIBCUDACXX part).
 The files are created in ${LIBCUDACXX_ROOT}/libcxx/build/...
 and the folder structure is described in the above information.
 I thought that there should be a modification for "LIBCXX_LIT_SITE_CONFIG" in perform_tests.bash

=========================

By the way, I saw the same build command for Windows part. Is it expected?

[wmaxey]

variable "LIBCXX_LIT_SITE_CONFIG" in perform_tests.bash seems to need to be ${LIBCUDACXX_PATH}/libcxx/build/test/lit.site.cfg but not ${LIBCUDACXX_PATH}/libcxx/build/libcxx/test/lit.site.cfg

That script should be correct. There are two separate lit configs created depending on which tests have been enabled.
LIBCXX_LIT_SITE_CONFIG and LIBCUDACXX_LIT_SITE_CONFIG.
The documentation will need to be updated to reflect that as well.

Hi Wesley,

 Yes. I tried to ENABLE_LIBCXX_TESTS and it made a build for LIBCXX part (not LIBCUDACXX part).
 The files are created in ${LIBCUDACXX_ROOT}/libcxx/build/...
 and the folder structure is described in the above information.
 I thought that there should be a modification for "LIBCXX_LIT_SITE_CONFIG" in perform_tests.bash

=========================

By the way, I saw the same build command for Windows part. Is it expected?

Sorry, I should clarify:

Lit consumes these two variables, not the ones I listed in the comments.
LIBCUDACXX_SITE_CONFIG = ${LIBCUDACXX_LIT_SITE_CONFIG}
LIBCXX_SITE_CONFIG = ${LIBCXX_LIT_SITE_CONFIG}

The environment vars are actually assigned later in the test script. I would like to update perform_tests.bash to do just one CMake config, but I didn't want to modify it more in case those outputs are relied on in DVS and such.

The Windows build commands are simplified in the same way though we don't support running libcxx tests yet.

[wmaxey]

I can't comment on the line, but is apt-get -y install llvm needed anymore?

Yep, as stated it's still need for cmake modules :)

This may not be required at this point actually. Part of the earlier build changes were to remove our reliance on them.

However, I won't be removing the instruction as I haven't tested on a clean system yet. On Windows cloning llvm-project is no longer required at least.