[flang-commits] [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)

[via flang-commits]

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@@ -419,10 +419,28 @@ RT_API_ATTRS bool RealOutputEditing<KIND>::EditEorDOutput(
     if (totalLength > width || !exponent) {
       return EmitRepeated(io_, '*', width);
     }
-    if (totalLength < width && digitsBeforePoint == 0 &&
-        zeroesBeforePoint == 0) {
-      zeroesBeforePoint = 1;
-      ++totalLength;
+    if (digitsBeforePoint == 0 && zeroesBeforePoint == 0 && scale <= 0) {
+      // Optional leading zero position (F202X leading zero control).
+      // When scale > 0 (kP with k > 0), digits are moved before the decimal
+      // point, so the leading zero position is not optional -- skip this.
+      // Value has no digits before the decimal point: "0.xxxE+yy" vs ".xxxE+yy"
+      switch (edit.modes.leadingZero) {
+      case MutableModes::LeadingZeroMode::Print:
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laoshd wrote:

Ok. I re-implemented it with editingFlags replacing enum, and made it match this request. Would you review it again please.

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