[PATCH] D98856: Always emit error for wrong interfaces to scalable vectors, unless cmdline flag is passed.

[Sander de Smalen via Phabricator via cfe-commits]

sdesmalen added inline comments.


================
Comment at: clang/lib/Driver/ToolChains/Clang.cpp:5052-5055
+  if (isa<BackendJobAction>(JA)) {
+    CmdArgs.push_back("-mllvm");
+    CmdArgs.push_back("-treat-scalable-fixed-error-as-warning");
+  }
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paulwalker-arm wrote:
> Are there any concerns related to LTO here? Could we live with LTO triggering errors for the invalid uses?  Part of me thinks this is reasonable given the clang exception is more about ensuring we can continue active development until we're ready to press the "it's supported" switch.
> Are there any concerns related to LTO here?
Yes, probably.

> Could we live with LTO triggering errors for the invalid uses? Part of me thinks this is reasonable given the clang exception is more about ensuring we can continue active development until we're ready to press the "it's supported" switch.
Yes, that's my thinking about this as well. When the compiler is ready  to be used in production, then an actual runtime compiler error (the default) would be appropriate which would lead to a bug-report that'd we need to go off and fix. During development of scalable vector support, we just want to have some extra flexibility, because we know not all code-paths are covered. So while we use it for those purposes, the recommendation is not to use LTO.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D98856/new/

https://reviews.llvm.org/D98856