[PATCH] [compiler-rt] Avoid undefined behaviour in __floatsisf and __floatsidf

[Tim Northover via llvm-commits]

On 2 November 2015 at 04:05, Stephen Canon via llvm-commits
<llvm-commits at lists.llvm.org> wrote:
>         3. implicit convert back to signed in (UB because -INT_MIN cannot be represented as int).

I think this is actually implementation-defined: C99 6.3.1.3p3
"Otherwise, if the new type is signed and the value cannot be
represented in it; either the result is implementation-defined or an
implementation-defined signal is raised.".

> The approach that I suggested before avoids this problem by having the result type of the absolute value operation be unsigned.

That looks like it'd work too, of course.

Cheers.

Tim.