[clang] [analyzer] Recognize missing MPI collectives in MPI-Checker (PR #209263)

[Balázs Benics via cfe-commits]

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@@ -174,6 +174,48 @@ void MPIFunctionClassifier::initCollectiveIdentifiers(ASTContext &ASTCtx) {
   MPINonBlockingTypes.push_back(IdentInfo_MPI_Ialltoall);
   MPIType.push_back(IdentInfo_MPI_Ialltoall);
   assert(IdentInfo_MPI_Ialltoall);
+
+  // Register the remaining standard collectives. These are not referenced by
+  // any of the individual is<Kind>Type() predicates, so they don't need a
+  // dedicated IdentifierInfo member; the checker only relies on them being
+  // classified as collective / nonblocking. All nonblocking (MPI_I...)
+  // variants take an MPI_Request as their last argument.
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steakhal wrote:

>The comment isn't clear that the reason why "these are not referenced by any of the individual isType() predicates" is simply because the checks for them aren't implemented.
You are right. And I think that's fine, so I'd probably just drop this comment.

I don't think we should invest into this checker unless we have real demand for it - and someone to push for it too. As this is outside of my expertise - it's very likely I wouldn't.

https://github.com/llvm/llvm-project/pull/209263