[flang] [llvm] [flang][flang-rt] Implement F202X leading-zero control edit descriptors LZ, LZS, and LZP for formatted output (F, E, D, and G editing) (PR #183500)

[Peter Klausler via llvm-commits]

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@@ -44,6 +44,12 @@ struct MutableModes {
     return editingFlags & decimalComma ? char32_t{','} : char32_t{'.'};
   }
 
+  enum class LeadingZeroMode : std::uint8_t {
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klausler wrote:

This could just be a new editing flag, like BN or DP.

https://github.com/llvm/llvm-project/pull/183500