[Bug c/90293] New: New function attribute: expect_return

[bugzi...@poradnik-webmastera.com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90293

            Bug ID: 90293
           Summary: New function attribute: expect_return
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: bugzi...@poradnik-webmastera.com
  Target Milestone: ---

I have an idea of new function attribute: expect_return. It would allow to
specify value usually returned from function, so it could help with
optimization in similar way like __builtin_expect() does.

Example use:

__attribute__((expect_return(false)))
bool DebugModeEnabled();

__attribute__((expect_return(false)))
bool IsErrorCode(int code);