https://gcc.gnu.org/bugzilla/show_bug.cgi?id=124655
Bug ID: 124655
Summary: Invalid string literal concatenation is accepted
inside of ignored attributes
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: luigighiron at gmail dot com
Target Milestone: ---
The following code is incorrectly accepted by GCC:
[[unknown::attribute(L""U"")]]int main(){}
> If a sequence of adjacent string literal tokens includes prefixed string
> literal tokens, the prefixed tokens shall all have the same prefix.
Section 6.4.5 "String literals" Paragraph 2 ISO/IEC 9899:2024
L""U"" is invalid even in ignored attributes. Clang and MSVC have the same
issue. This issue also applies to C++ when a space is added between the string
literals L"" U"", including in Clang and MSVC too. EDG rejects L"" U"" even in
ignored attributes. MSVC even accepts it in attributes that are not ignored,
for example [[nodiscard(L"" U"")]].
