[Bug tree-optimization/94166] [10 Regression] random -fcompare-debug failures since r10-1913

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94166

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Oops, I've screwed up, the commit log should have been:
reassoc: Avoid code generation to depend on hash_map traversal [PR94166]

On the following testcase, if there is ASLR, the compiler generates             
different code each time (out of 1000 invocations 994 unique assembler          
contents).  The problem is that undistribute_bitref_for_vector uses             
a hash_map from a tree (SSA_NAME) to a vector and such a hash_map is            
by default doing pointer hashing on the SSA_NAME rather than using              
something stable (SSA_NAME_VERSION).                                            
One possible way would be to use SSA_NAME_VERSION as hash function,             
but given that we from the hash_map traversal just populate a vector            
which is then sorted, I think it is easier to make the sort callback            
use SSA_NAME_VERSION as secondary sorting key and thus ensure stable            
sort (that is generally desirable anyway).                                      

instead.  Sorry.