[flang][build] Fixed paths discrovery for the out-of-tree build. #87822
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When building flang out-of-tree with relative paths in LLVM_DIR, CLANG_DIR and MLIR_DIR, we need to compute the absolute paths based on the CMake build directory (i.e. where the cmake is invoked from).
| @@ -81,12 +81,13 @@ if (FLANG_STANDALONE_BUILD) | |||
| mark_as_advanced(LLVM_ENABLE_ASSERTIONS) | |||
| endif() | |||
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| # We need a pre-built/installed version of LLVM. | |||
| find_package(LLVM REQUIRED HINTS "${LLVM_CMAKE_DIR}") | |||
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This use of LLVM_CMAKE_DIR does not make much sense to me, because it is set by LLVMConfig.cmake which is not in effect before this find_package command executes.
| @@ -97,7 +98,7 @@ if (FLANG_STANDALONE_BUILD) | |||
| CLANG_DIR_ABSOLUTE | |||
| ${CLANG_DIR} | |||
| REALPATH | |||
| ${CMAKE_CURRENT_SOURCE_DIR}) | |||
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Seems like BASE_DIR was meant to be used here.
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This commit is breaking this buildbot: https://lab.llvm.org/buildbot/#/builders/175 Could you please take a look? |
I do not know how I missed that breakage. Thank you for letting me know, @ceseo! I will look immediately. |
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I see what happened. This change actually fixed handling of the relative paths, but this buildbot was using a trick to workaround the issue that was fixed. The buildbot builds LLVM tree here: And it is run from The buildbot needs to be fixed, since we can now use "real" paths relative to the Flang build directory. |
After llvm/llvm-project#87822 we can specify real relative paths from the flang build directory to the directories containing LLVM/CLANG/etc. projects' config files.
After llvm/llvm-project#87822 we can specify real relative paths from the flang build directory to the directories containing LLVM/CLANG/etc. projects' config files.
…ld. (llvm#87822)" This reverts commit 215eee6.
…uilds The changes in llvm#87822 introduced a regression where Flang could no longer be built standalone without explicitly specifying all of LLVM_DIR, CLANG_DIR and MLIR_DIR. Restore the earlier logic that used these paths as hints, and supported finding system-wide LLVM install via default paths. Instead, make paths absolute after locating the packages, using the paths CMake determined.
…uilds (#120914) The changes in #87822 introduced a regression where Flang could no longer be built standalone without explicitly specifying all of LLVM_DIR, CLANG_DIR and MLIR_DIR. Restore the earlier logic that used these paths as hints, and supported finding system-wide LLVM install via default paths. Instead, make paths absolute after locating the packages, using the paths CMake determined. ----- @vzakhari, could you confirm that this doesn't break your use case?
…uilds (llvm#120914) The changes in llvm#87822 introduced a regression where Flang could no longer be built standalone without explicitly specifying all of LLVM_DIR, CLANG_DIR and MLIR_DIR. Restore the earlier logic that used these paths as hints, and supported finding system-wide LLVM install via default paths. Instead, make paths absolute after locating the packages, using the paths CMake determined. ----- @vzakhari, could you confirm that this doesn't break your use case?
When building flang out-of-tree with relative paths in LLVM_DIR,
CLANG_DIR and MLIR_DIR, we need to compute the absolute paths
based on the CMake build directory (i.e. where the cmake is invoked
from).