[Bug rtl-optimization/77425] Pointer test follows dereference in sched-int.h

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=77425

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

           What    |Removed                     |Added
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                 CC|                            |jakub at gcc dot gnu.org

--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 39534
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=39534&action=edit
gcc7-pr77425.patch

Untested fix.  I believe if we are going to return false, then nothing
is/should be looking at the iterator object anymore, at least all other uses of
linkp field dereference it anyway and for NULL list &list->first gives an UB
NULL pointer.