On Linux, FreeBSD and other systems I have valgrind for checking for memory errors like invalid reads and similar. I really love valgrind. Now I have to test code on Solaris
Since version 3.11.0, Valgrind does run on Solaris. See Release Notes and Supported Platforms.
More precisely, x86/Solaris and amd64/Solaris is now supported. Support for sparc/Solaris is still in works.
watchmalloc is a quite useful library that can be dynamically loaded for your program (usually no need for recompiling) and then sets watchpoints at all the usually problematic memory locations, like freed areas or after an allocated memory block. If your program accesses one of these invalid areas it gets a signal and you can inspect it in the debugger.
Depending on the configuration problematic areas can be watched for writes only, or also for reads.
The dbx included with the Sun Studio compilers includes memory access checking support in its "Run Time Checking" feature (the check
subcommand). See:
The related "Sun Memory Error Discovery Tool" is also available from http://cooltools.sunsource.net/discover/