[clang] [clang] increase default constexpr step limit (PR #143785)

[via cfe-commits]

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@@ -3992,7 +3992,7 @@ Controlling implementation limits
   Sets the limit for the number of full-expressions evaluated in a single
   constant expression evaluation. This also controls the maximum size
   of array and dynamic array allocation that can be constant evaluated.
-  The default is 1048576.
+  The default is 20000000.
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Tsche wrote:

How do you feel about using the C++ digit separator `'` to instead spell it as 20'000'000?

https://github.com/llvm/llvm-project/pull/143785