[Lldb-commits] [PATCH] D56531: [CMake] Replace use of llvm-config with LLVM and Clang CMake packages

[Pavel Labath via Phabricator via lldb-commits]

labath added a comment.

In D56531#1355794 <https://reviews.llvm.org/D56531#1355794>, @sgraenitz wrote:

> In D56531#inline-500764 <https://reviews.llvm.org/D56531#inline-500764>, @labath wrote:
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> > it should be possible to build lldb against an already-installed llvm
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> In D56531#inline-501059 <https://reviews.llvm.org/D56531#inline-501059>, @xiaobai wrote:
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> > When I wrote this I thought that it is possible to build against an installed LLVM, but I don't think that's currently possible. For example [...]
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> IIUC all LLVM subprojects are made for *testing* against the build-tree. LLDB tests depend on LLVMTestingSupport and others that are not part of the installed package (see `LLVM_EXPORTS_BUILDTREE_ONLY`). 
>  While the ability to *build* against an installed LLVM sounds like a good goal in principle, it's questionable what benefit it has without the ability to *test* the result. Thus, I wouldn't consider it a high prio for now.


The fact that in is not possible to test lldb when using an installed llvm is unfortunate, but I think it would be nice to preserve the ability to build it at least, as this is what (some? i am not sure about other distros, but this is at least true for gentoo) linux distros use to provide modular llvm packages. If you still wanted to provide modular packages from a monolithic build you'd have to go through the install tree manually and sort the artefacts into respective packages, defeating the purpose of the install tree.

(This is also the use case for having separated llvm and clang and then building lldb against those.)


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  https://reviews.llvm.org/D56531/new/

https://reviews.llvm.org/D56531