Hi!
The last argument to strncasecmp is incorrect, so it matched even when
can%' wasn't followed by t. Also, the !ISALPHA (format_chars[1]) test
looks pointless, format_chars[1] must be ' if strncasecmp succeeded and
so will never be ISALPHA.
Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for
trunk?
2020-02-10 Jakub Jelinek <ja...@redhat.com>
PR other/93641
* c-format.c (check_plain): Fix up last argument of strncasecmp.
Remove useless extra test.
* gcc.dg/format/gcc_diag-11.c (test_cdiag_bad_words): Add two further
tests.
--- gcc/c-family/c-format.c.jj 2020-01-12 11:54:36.202416592 +0100
+++ gcc/c-family/c-format.c 2020-02-10 10:03:49.224547303 +0100
@@ -3270,8 +3270,7 @@ check_plain (location_t format_string_lo
"quoted %qs directive in format; "
"use %qs instead", "%s", "%qs");
else if (format_chars - orig_format_chars > 2
- && !strncasecmp (format_chars - 3, "can%'t", 5)
- && !ISALPHA (format_chars[1]))
+ && !strncasecmp (format_chars - 3, "can%'t", 6))
format_warning_substr (format_string_loc,
format_string_cst,
fmtchrpos - 3, fmtchrpos + 3, opt,
--- gcc/testsuite/gcc.dg/format/gcc_diag-11.c.jj 2020-01-12
11:54:37.423398171 +0100
+++ gcc/testsuite/gcc.dg/format/gcc_diag-11.c 2020-02-10 10:04:50.594632918
+0100
@@ -400,6 +400,8 @@ void test_cdiag_bad_words (tree t, gimpl
cdiag ("you can't do that"); /* { dg-warning "contraction 'can't' in format"
} */
cdiag ("you can%'t do that");/* { dg-warning "contraction 'can%'t' in
format" } */
cdiag ("Can%'t touch this.");/* { dg-warning "contraction 'Can%'t' in
format" } */
+ cdiag ("can%'");
+ cdiag ("can%' whatever");
cdiag ("on the commandline");/* { dg-warning "misspelled term 'commandline'
in format; use 'command line' instead" } */
cdiag ("command line option");/* { dg-warning "misspelled term 'command line
option' in format; use 'command-line option' instead" } */
cdiag ("it mustn't be"); /* { dg-warning "contraction 'mustn't' in
format" } */
Jakub
