fix: use higher priority when installing llvm alternatives #223
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
before this change, gcc and g++ are installed using
updateAptAlternatives()
with the same priority of 40 when they are installed along with ld and libstdc++ as the dependencies of clang and llvm. but both gcc and clang are installed using the same priority of 40 on ubuntu, and the same applies to g++ and clang++. this renders it impossible to use the default compilers of cc and cxx when clang/llvm is installed using setup-cpp on an ubuntu host, as gcc is always prefered over clang by the update-alternatives, as their priorities are identical.in this change, the "priority" parameter is added to the setupGcc(), so that we can specify a different priority when installing llvm. strictly speaking, this is not necessary. as we can just use a higher priority when calling updateAptAlternatives() in llvm/llvm.ts. but by making it more explicit, we can ensure that we always prefer llvm over gcc when installing llvm.