Memory access errors are a major source of bugs in programs written in C. 
The errors are difficult to find and can lead to runtime failures or even
security compromises.  Languages such as Java are free from such errors
because of their strong type-checking mechanisms.  We propose a method to
achieve many of the memory safety features in these type-safe languages
without changing the C language or rewriting source code.  Our approach is
based on the safety rule that a memory variable should only be updated by
the small set of instructions intended by the programmer.  Any deviation
from the safety rule is considered a violation.  The proposed method is
implemented using static program slicing techniques and runtime memory
access monitoring.  Our method can be used for detecting memory corruption
attacks, identifying bugs during software development, and diagnosing
memory-related failures post-mortem.