[clang] [llvm] Option to control signaling NaN support (PR #193055)

[Serge Pavlov via cfe-commits]

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@@ -2574,6 +2574,14 @@ For example:
 ``sanitize_alloc_token``
     This attribute indicates that implicit allocation token instrumentation
     is enabled for this function.
+``signaling-nans``
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spavloff wrote:

You are right, "no-signaling-nans" is a restriction. If, however we choose "signaling-nans" as a default state, it would mean that the same set of attributes would change meaning in many cases. For instance, the default mode code would imply "signaling-nans", it could break backward compatibility.

https://github.com/llvm/llvm-project/pull/193055