Re: older gccs and case labels producing integer constants

[Richard Biener]

On Tue, 5 Apr 2022, Borislav Petkov wrote:

> On Tue, Apr 05, 2022 at 12:06:45PM +0200, Richard Biener wrote:
> > Wird auch mit gcc 11 rejected.  Kanns sein dass mit gcc 7 andere
> > compiler flags genommen werden?
> 
> Found it:
> 
> $ gcc -fsanitize=shift -c switch.c
> switch.c: In function ‘foo’:
> switch.c:10:7: error: case label does not reduce to an integer constant
>        case (((0xfc08) << 16) | (0x0101)):;
> 
> $ gcc --version
> gcc (SUSE Linux) 7.4.1 20190905 [gcc-7-branch revision 275407]
> Copyright (C) 2017 Free Software Foundation, Inc.
> 
> Something not fully backported?

Probably early vs. late folding change in the frontend.  So yes,
don't use -fsanitize=... ;)

Richard.

-- 
Richard Biener <rguenther@xxxxxxx>
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