minmax: allow min()/max()/clamp() if the arguments have the same signedness.

The type-check in min()/max() is there to stop unexpected results if a
negative value gets converted to a large unsigned value.  However it also
rejects 'unsigned int' v 'unsigned long' compares which are common and
never problematc.

Replace the 'same type' check with a 'same signedness' check.

The new test isn't itself a compile time error, so use static_assert() to
report the error and give a meaningful error message.

Due to the way builtin_choose_expr() works detecting the error in the
'non-constant' side (where static_assert() can be used) also detects
errors when the arguments are constant.

Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: David Laight <[email protected]>
Cc: Andy Shevchenko <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Cc: Jason A. Donenfeld <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Matthew Wilcox (Oracle) <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>

0 files changed, 0 insertions, 0 deletions