a question about const and pure functions.

[Kenneth Zadeck]

Do we mark functions being const or pure (TREE_READONLY or DECL_IS_PURE) 
based on some external standard definition or are these defined any way 
that the gcc community feels is good?  

I am in the process of moving the code that does this analysis so that 
it is done very early and at once for the entire compilation unit.  
There appear to be a few minor bugs in the code as well as a few missed 
opportinities.  But before I was going to make any changes, I was 
wondering if there was any better standard of definition beyond what is 
defined in doc/extend.texi.

Kenny