-fdelete-null-pointer-checks
Use global dataflow analysis to identify and eliminate useless checks for null pointers. The compiler assumes that dereferencing a null pointer would have halted the program. If a pointer is checked after it has already been dereferenced, it cannot be null.
In some environments, this assumption is not true, and programs can safely dereference null pointers. Use -fno-delete-null-pointer-checks to disable this optimization for programs which depend on that behavior.
[^] # Re: Je ne comprends pas
Posté par Mathieu Schroeter (site web personnel, Mastodon) . En réponse à la dépêche Exploit local dans le noyau Linux 2.6.30. Évalué à 3.
-fdelete-null-pointer-checks
Use global dataflow analysis to identify and eliminate useless checks for null pointers. The compiler assumes that dereferencing a null pointer would have halted the program. If a pointer is checked after it has already been dereferenced, it cannot be null.
In some environments, this assumption is not true, and programs can safely dereference null pointers. Use -fno-delete-null-pointer-checks to disable this optimization for programs which depend on that behavior.
Enabled at levels -O2, -O3, -Os.