diff options
authorRich Felker <>2014-09-05 03:28:00 -0400
committerRich Felker <>2014-09-05 03:28:00 -0400
commit4674809bdf7a46041ac0152eea0a6363ceeca548 (patch)
parentfff546930347d99729f1c0a9d911e7f24a094531 (diff)
fix case mapping for U+00DF (ß)
U+00DF ('ß') has had an uppercase form (U+1E9E) available since Unicode 5.1, but Unicode lacks the case mappings for it due to stability policy. when I added support for the new character in commit 1a63a9fc30e7a1f1239e3cedcb5041e5ec1c5351, I omitted the mapping in the lowercase-to-uppercase direction. this choice was not based on any actual information, only assumptions. this commit adds bidirectional case mappings between U+00DF and U+1E9E, and removes the special-case hack that allowed U+00DF to be identified as lowecase despite lacking a mapping. aside from strong evidence that this is the "right" behavior for real-world usage of these characters, several factors informed this decision: - the other "potentially correct" mapping, to "SS", is not representable in the C case-mapping system anyway. - leaving one letter in lowercase form when transforming a string to uppercase is obviously wrong. - having a character which is nominally lowercase but which is fixed under case mapping violates reasonable invariants.
2 files changed, 1 insertions, 2 deletions
diff --git a/src/ctype/iswlower.c b/src/ctype/iswlower.c
index c754fb95..79df44a3 100644
--- a/src/ctype/iswlower.c
+++ b/src/ctype/iswlower.c
@@ -3,7 +3,7 @@
int iswlower(wint_t wc)
- return towupper(wc) != wc || wc == 0xdf;
+ return towupper(wc) != wc;
int __iswlower_l(wint_t c, locale_t l)
diff --git a/src/ctype/towctrans.c b/src/ctype/towctrans.c
index 5e0889b1..6af61875 100644
--- a/src/ctype/towctrans.c
+++ b/src/ctype/towctrans.c
@@ -151,7 +151,6 @@ static const unsigned short pairs[][2] = {
{ 0x03f7, 0x03f8 },
{ 0x03fa, 0x03fb },
{ 0x1e60, 0x1e9b },
- { 0xdf, 0xdf },
{ 0x1e9e, 0xdf },
{ 0x1f59, 0x1f51 },