[committed] libstdc++: Check for multiple modifiers in chrono format string [PR110708]
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Commit Message
Tested x86_64-linux. Pushed to trunk.
This should be backported to gcc-13 too, but it can wait until 13.3
(it's just an accepts-invalid and unlikely to affect anybody in
practice).
-- >8 --
The logic for handling modified chrono specs like %Ey was just
restarting the loop after each modifier, and not checking whether we'd
already seen a modifier.
libstdc++-v3/ChangeLog:
PR libstdc++/110708
* include/bits/chrono_io.h (__formatter_chrono::_M_parse): Only
allow a single modifier.
* testsuite/std/time/format.cc: Check multiple modifiers.
---
libstdc++-v3/include/bits/chrono_io.h | 5 +++++
libstdc++-v3/testsuite/std/time/format.cc | 10 ++++++++++
2 files changed, 15 insertions(+)
@@ -426,6 +426,11 @@ namespace __format
break;
case 'O':
case 'E':
+ if (__mod) [[unlikely]]
+ {
+ __allowed_mods = _Mod_none;
+ break;
+ }
__mod = __c;
continue;
default:
@@ -68,6 +68,16 @@ test_bad_format_strings()
// modifier not valid for conversion specifier
VERIFY( not is_format_string_for("{:%Ea}", t) );
VERIFY( not is_format_string_for("{:%Oa}", t) );
+
+ // more than one modifier (PR libstdc++/110708)
+ VERIFY( not is_format_string_for("{:%EEc}", t) );
+ VERIFY( not is_format_string_for("{:%EEEc}", t) );
+ VERIFY( not is_format_string_for("{:%OOd}", t) );
+ VERIFY( not is_format_string_for("{:%OOOd}", t) );
+ VERIFY( not is_format_string_for("{:%EEy}", t) );
+ VERIFY( not is_format_string_for("{:%OOy}", t) );
+ VERIFY( not is_format_string_for("{:%OEy}", t) );
+ VERIFY( not is_format_string_for("{:%EOy}", t) );
}
template<typename I>