------- Comment #3 from mick at nag dot co dot uk 2005-10-11 09:26 ------- Thanks - the problem is now fixed in 64-bit compilations. However, if I compile try.f and sub.c with the -m32 flag, I still get memory allocated on 8-byte boundaries rather than 16-byte. As Andrew said, this is down to the way glibc malloc behaves. I see that the glibc folks have discussed this before, also in relation to the use of SSE instructions, but don't intend to change the way malloc works:
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15795 After reading that discussion it's not entirely clear to me why there is so much objection to 16-byte alignment, but whatever, it leaves me in the position of having lots of SSE assembly code that I can only use from Fortran by kludges like this: allocate(workspace(1000)) if (is_on_16_byte_boundary(workspace)) then call assembly_routine(workspace) else if (is_on_8_byte_boundary(workspace)) then call assembly_routine(workspace(3)) end if Personally I think that the malloc in glibc should align to 16 bytes, but given that it sounds like that's not likely to happen, another way might be for gfortran to use memalign instead of malloc in its ALLOCATE routine. -- mick at nag dot co dot uk changed: What |Removed |Added ---------------------------------------------------------------------------- Status|RESOLVED |UNCONFIRMED Resolution|FIXED | http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24261
