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| author | Bruno Haible <bruno@clisp.org> | 2021-01-07 02:06:17 +0100 |
|---|---|---|
| committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2021-02-04 16:44:24 -0300 |
| commit | 1b3fc33f810b605e0e6dfcba96dddae432ccaab3 (patch) | |
| tree | 00ef0dc42d3fb920c9294b9b90bbfe0f74aa7414 | |
| parent | 5ec029c8835b71d7a3d6036c9358198b4d9e59fc (diff) | |
| download | glibc-1b3fc33f810b605e0e6dfcba96dddae432ccaab3.zip glibc-1b3fc33f810b605e0e6dfcba96dddae432ccaab3.tar.gz glibc-1b3fc33f810b605e0e6dfcba96dddae432ccaab3.tar.bz2 | |
argp: Don't rely on undefined behaviour of _tolower().
Patch by Eric Blake
<https://lists.gnu.org/archive/html/bug-gnulib/2009-09/msg00287.html>.
* argp/argp-help.c (hol_entry_cmp): Don't use _tolower on values that are
not upper-case. Pass correct range to tolower.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
| -rw-r--r-- | argp/argp-help.c | 10 |
1 files changed, 4 insertions, 6 deletions
diff --git a/argp/argp-help.c b/argp/argp-help.c index f417e12..5844d5b 100644 --- a/argp/argp-help.c +++ b/argp/argp-help.c @@ -780,13 +780,11 @@ hol_entry_cmp (const struct hol_entry *entry1, first, but as they're not displayed, it doesn't matter where they are. */ { - char first1 = short1 ? short1 : long1 ? *long1 : 0; - char first2 = short2 ? short2 : long2 ? *long2 : 0; -#ifdef _tolower - int lower_cmp = _tolower (first1) - _tolower (first2); -#else + unsigned char first1 = short1 ? short1 : long1 ? *long1 : 0; + unsigned char first2 = short2 ? short2 : long2 ? *long2 : 0; + /* Use tolower, not _tolower, since the latter has undefined + behaviour for characters that are not uppercase letters. */ int lower_cmp = tolower (first1) - tolower (first2); -#endif /* Compare ignoring case, except when the options are both the same letter, in which case lower-case always comes first. */ return lower_cmp ? lower_cmp : first2 - first1; |