https://gcc.gnu.org/bugzilla/show_bug.cgi?id=126977
Bug ID: 126977
Summary: [17 Regression] factor_out_conditional_operation
breaks __builtin_crc* handling
Product: gcc
Version: 17.0
Status: UNCONFIRMED
Keywords: rejects-valid
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: pinskia at gcc dot gnu.org
Reporter: pinskia at gcc dot gnu.org
Target Milestone: ---
Created attachment 65381
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=65381&action=edit
testcase
The attached testcase should compile but on the trunk we get:
<source>: In function 'crc32_data32':
<source>:2:5: error: third argument to 'crc' builtins must be a constant
2 | int crc32_data32 (unsigned x, unsigned y, int z)
| ^~~~~~~~~~~~
This is because for the 3rd operand of the __builtin_crc* __builtin_rev_crc*
builtins is special and need to be a constant.
Noticed while reviewing
https://gcc.gnu.org/pipermail/gcc-patches/2026-August/728405.html .
