Revert implementation of Tcl_UniCharAtIndex() change done in this commit: [6596c4af31e29b5d]. Just look at the Tcl_UtfAtIndex() implementation for TCL_UTF_MAX=4: It's not the same.

There are no test-cases for Tcl_UniCharAtIndex(), see [f45d0dc1a7], not really worth to write one, since the implementation of this function didn't change in 20 years.

1 files changed, 3 insertions, 1 deletions

diff --git a/generic/tclUtf.c b/generic/tclUtf.c
index 9596aed..c7f8a94 100644
--- a/generic/tclUtf.c
+++ b/generic/tclUtf.c
@@ -937,7 +937,9 @@ Tcl_UniCharAtIndex(
 {
     Tcl_UniChar ch = 0;
 
-    TclUtfToUniChar(Tcl_UtfAtIndex(src, index), &ch);
+    while (index-- >= 0) {
+	src += TclUtfToUniChar(src, &ch);
+    }
     return ch;
 }