Some compilers accept recursive comments without any warnings. The Compiler will issue a warning for each such recursive comment:
/* this is a recursive comment /*
int a;
/* */
The Compiler will treat the above source completely as one single comment, so the definition of `a' is inside the comment. That is, the Compiler treats everything between the first opening comment ` /*' until the closing comment token ` */' as a comment. If there are such recursive comments, correct them.