https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94587
Bug ID: 94587
Summary: Intrinsics optimization bug with -O2
-march=skylake-avx512
Product: gcc
Version: 9.3.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: rtl-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: lopresti at gmail dot com
Target Milestone: ---
Created attachment 48265
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=48265&action=edit
Minimal test case for skylake-avx512 intrinsics optimization bug
This bug appears to be present across at least GCC 8 and GCC 9.
Compile the attached program using "g++ -O2 -march=skylake-avx512" and run it.
Expected result: No output, exit status 0.
Actual result: "WRONG -0.99999999999999789058", exit status 2.
To make the problem go away, do any of the following:
- Use "-march=corei7" ; or
- Remove the "__attribute__((noinline))" from the rot90() function ; or
- Add "-DHEISENBUG" to the command line
