https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65685
Bug ID: 65685
Summary: Reducing alignment with alignas should be rejected
Product: gcc
Version: 5.0
Status: UNCONFIRMED
Keywords: accepts-invalid
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: redi at gcc dot gnu.org
Blocks: 58601
GCC doesn't give any diagnostic for the example in 7.6.2 [dcl.align] p5:
The combined effect of all alignment-specifiers in a declaration shall not
specify an alignment that is less strict than the alignment that would be
required for the entity being declared if all alignment-specifiers
appertaining to that entity were omitted. [ Example:
struct alignas(8) S {};
struct alignas(1) U {
S s;
}; // Error: U specifies an alignment that is less strict than
// if the alignas(1) were omitted.
— end example ]
