[libc-commits] [libc] [libc] Support %lc in printf (PR #169983)

[Shubh Pachchigar via libc-commits]

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@@ -33,7 +41,27 @@ LIBC_INLINE int convert_char(Writer<write_mode> *writer,
     RET_IF_RESULT_NEGATIVE(writer->write(' ', padding_spaces));
   }
 
-  RET_IF_RESULT_NEGATIVE(writer->write(c));
+#ifndef LIBC_COPT_PRINTF_DISABLE_WIDE
+  if (to_conv.length_modifier == LengthModifier::l) {
+    wint_t wi = static_cast<wint_t>(to_conv.conv_val_raw);
+
+    if (wi == WEOF) {
+      return -1;
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shubhe25p wrote:

Or let me know if you want me to introduce two new error codes like `ILLEGAL_WIDE_CHAR` for WEOF
`MB_CONVERSION_ERROR` for wcrtomb failure which maps to EILSEQ in internal_error_to_errno?

https://github.com/llvm/llvm-project/pull/169983