https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108768
Bug ID: 108768
Summary: bogus -Warray-bounds warnings
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c
Assignee: unassigned at gcc dot gnu.org
Reporter: mi+gcc at aldan dot algebra.com
Target Milestone: ---
Created attachment 54453
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=54453&action=edit
Test case (otpcode.c after passing preprocessor)
Compiling the attached file (part of TCL-TRF package) with:
gcc12 -O2 -Wall -Werror -c otpcode.i -o otpcode.o
You'll get:
In function 'extract',
inlined from 'FlushDecoder' at otpcode.i:6170:21:
otpcode.i:6262:9: error: array subscript 9 is outside array bounds of 'char[9]'
[-Werror=array-bounds]
6262 | cc = s[start/8 +1];
| ~^~~~~~~~~~~~
otpcode.i: In function 'FlushDecoder':
otpcode.i:6131:8: note: at offset 9 into object 'b' of size 9
6131 | char b[9];
| ^
In function 'extract',
inlined from 'FlushDecoder' at otpcode.i:6170:21:
otpcode.i:6263:9: error: array subscript 10 is outside array bounds of
'char[9]' [-Werror=array-bounds]
6263 | cr = s[start/8 +2];
| ~^~~~~~~~~~~~
otpcode.i: In function 'FlushDecoder':
otpcode.i:6131:8: note: at offset 10 into object 'b' of size 9
6131 | char b[9];
| ^
Note, how the "start/8 + 1" is being misread as "9"...
