https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101949
Bug ID: 101949
Summary: git miscompiled with -flto -fipa-pta
Product: gcc
Version: 11.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: other
Assignee: unassigned at gcc dot gnu.org
Reporter: alex_y_xu at yahoo dot ca
Target Milestone: ---
Created attachment 51313
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=51313&action=edit
step 2 patch
steps to reproduce:
1. download and unpack git-2.33.0 (other versions may also work)
2. apply the attached patch to work around binutils bugs with duplicate
function names
3. make CFLAGS="-O2 -flto -fipa-pta" git git-remote-https
4. git clone https://github.com/Hello71/empty-project.git
5. PATH=$PWD:$PATH git -C empty-project fetch
6. objdump --disassemble=iterate_ref_map2 git
expected behavior:
step 5 succeeds. in step 6, function references %rsi at some point
actual behavior:
step 5 segfaults. in step 6, function never references %rsi (i.e. returns 0
without populating *oid)
additional behavior:
it works ok without -flto or without -fipa-pta, thus the non-reduced test case.
note that the patch is only required for step 6; step 5 fails even if the patch
is not applied.
