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

[Matt Arsenault 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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arsenm wrote:

Attributes that impose restrictions are problematic. It's much better when the conservatively correct case is the default 

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