[Bug c/59708] clang-compatible checked arithmetic builtins

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=59708

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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  Attachment #33855|0                           |1
        is obsolete|                            |

--- Comment #12 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 33891
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=33891&action=edit
gcc5-pr59708-wip2.patch

Updated patch, this time __builtin_umul{,l,ll}_overflow should work fully, and
with the exception of widest type ({,un}signed __int128 on targets that do
support that, {,un}signed long long otherwise) also the type-generic variants.
What is still unhandled is in the widest type signed +- signed -> unsigned,
unsigned +- unsigned -> signed and mixed sign (either between operands, or
between operand and result) multiplication in the widest type.