rod.niner@xxxxxx writes: > Normally there are #defines build into compilers to detect compiler type, > version and chip types. > Is there a list of these some place > I seem to remember I could wrap code around an #ifdef _GNU so that when > the compiler would change I could alert others to compiler specific > sections of code. The exact set of predefined macros will vary depending on the command line arguments. You can see them by doing this: gcc -E -dD -x c /dev/null along with whatever other arguments you want to pass. gcc does not define _GNU, but it does define __GNUC__. Ian