Insure++ is a memory debugger computer program, used by software developers to detect various errors in programs written in C and C++. It is made by Parasoft, and is functionally similar to other memory debuggers, such as Purify, Valgrind and Dr Memory.
Overview
Insure++ can automatically find erroneous accesses to freed memory (use-after-free situations), array-bounds violations, freeing unallocated memory (which often happens when a programmer frees the same memory twice, or when he frees global or stack memory), and many others.
Unlike Purify and Valgrind, Insure++ inserts its instrumentation at the source-code level, which allows it to detect errors that the other tools miss. In particular, Insure++ can detect buffer overflows in automatic arrays, and overflows which involve pointers that accidentally "jump" from one valid memory region to another, as in the following example:
<syntaxhighlight lang="c">
- include <stdlib.h>
int main()
{
char *p = malloc(1024); /* first dynamically-allocated block */
char *q = malloc(1024); /* second block */
p += 1200; /* At this point, "p" is likely to point into the second block.
However, false assumptions about the real behaviour lead to mistakes. */
- p = 'a'; /* invalid write (past the end of the first block) */
}
</syntaxhighlight>
The source-level instrumentation allows it to not only identify that a leak occurred, but where it occurred.