[Bug target/52023] _Alignof (double) yields wrong value on x86

[joseph at codesourcery dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52023

--- Comment #10 from joseph at codesourcery dot com <joseph at codesourcery dot com> 2012-01-27 23:12:38 UTC ---
I don't think the test programs here are strictly conforming - the offset 
could be bigger than the alignment, and alignments are values 
"representing the number of bytes between successive addresses at which a 
given object can be allocated" which I don't think necessarily have 
literally to count bytes (they may be some other less direct encoding of 
alignment requirements that satisfies the requirements of 6.2.8).  But I 
think the bug is correct; alignof should return the least ABI alignment 
requirement for a type, which is the biggest requirement that the compiler 
can actually rely on when given a pointer to that type.