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Re: unable to detect exception model

On 6/25/06, Eric Botcazou <> wrote:
> So, something obviously wrong with
> struct max_alignment {
>  char c;
>  union {
>    long double d;
>  } u;
> };
> /* The biggest alignment required.  */
> #define MAX_ALIGNMENT (offsetof (struct max_alignment, u))
> for SPARC 32bit?

I don't think so, the ABI says 8 in both cases.

Note that bootstrap doesn't fail on SPARC/Solaris 2.[56] and (presumably)
SPARC/Linux, which have HOST_WIDE_INT == 32, whereas SPARC/Solaris 7+ have
HOST_WIDE_INT == 64.  All are 32-bit compilers.

Bootstrap doesn't fail on SPARC64/Solaris 7+ either, for which the ABI says 16
for the alignment in both cases.  They are 64-bit compilers.

SPARC psABI3.0 (32bit version) defines long double as 8 byte aligned. SCD4.2, 64bit version, defines long double as 16 byte aligned with some caveat (which essentially says long double can be 8-byte aligned in some cases - fortran common block case - but the compiler should assume 16-byte unless it can prove otherwise). On 32bit ABI, there's also a possiblity of "double"s being only 4-byte aligned when a double is passed on the stack.

I don't know enough about gcc's gc to know whether the above can trip it over,
but the memory allocation (malloc and the likes) shouldn't be a
problem as long as
it returns 8-byte aligned block on 32bit and 16-byte aligned on 64bit.
#pragma ident "Seongbae Park, compiler,";

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