https://gcc.gnu.org/bugzilla/show_bug.cgi?id=110617
--- Comment #11 from Florian Weimer <fw at gcc dot gnu.org> ---
(In reply to Xi Ruoyao from comment #10)
> But Zack's reason against using __nonnull is __nonnull may cause unwanted
> optimizations to *the user code*.
GCC already offers options to control function call behavior in the presence of
nonnull attributes:
For function calls:
• If the compiler determines that a null pointer is passed in an
argument slot marked as non-null, and the ‘-Wnonnull’ option
is enabled, a warning is issued. *Note Warning Options::.
• The ‘-fisolate-erroneous-paths-attribute’ option can be
specified to have GCC transform calls with null arguments to
non-null functions into traps. *Note Optimize Options::.
• The compiler may also perform optimizations based on the
knowledge that certain function arguments cannot be null.
These optimizations can be disabled by the
‘-fno-delete-null-pointer-checks’ option. *Note Optimize
Options::.
So I don't think we need another way to disable nonnull attributes in installed
glibc headers.
