[clang] [clang] Macro for constant rounding mode (PR #92699)

[Eli Friedman via cfe-commits]

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@@ -0,0 +1,55 @@
+// RUN: %clang_cc1 -emit-llvm -triple i386-linux -Wno-unknown-pragmas %s -o - | FileCheck %s
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efriedma-quic wrote:

Is there some reason the preprocessor can't parse FENV_ROUND?  Breaking code with -save-temps etc. seems bad.

https://github.com/llvm/llvm-project/pull/92699