make __dynamic_object_size system call overflow checks work without recompilation

[thestinger]

These checks should be moved inside the standard system call entry points, with different entry points without the checks used for libc itself. This would allow the same coverage without needing to recompile code, and it would eliminate the tiny code size increase.

[thestinger]

Adding this back results in strange linker errors due to duplicates of the malloc symbols defined in the malloc common code... it's quite strange.

[thestinger]

Adding this back results in strange linker errors due to duplicates of the malloc symbols defined in the malloc common code... it's quite strange.

[thestinger]

This is implemented.

[thestinger]

This is implemented.