Undefined return type (mis-)reported as fatal error

[Bob Green]

g++ 2.95.2 on Intel Solaris 2.6 (but the bug isn't platform dependent).

Try compiling code which declares funtions without explicit return
types. In the old C style, these functions implicitly return int.
E.G. try compiling Xlib.h. 

Normally g++ has command line flags -Wreturn-type or -pendantic which
enable a warning message about the missing return type. In 2.95.2 this
message is reported without the command line flags as a fatal error.
This makes compiling X11 programs a tad difficult.

I believe the error is in grokdeclarator in gcc/cp/decl.c near line 9835.

         if (in_system_header)
            /* Allow it, sigh.  */;
          else if (pedantic || ! is_main)
			    ^^
			     +----------------------------------------------wrong
            cp_pedwarn ("ANSI C++ forbids declaration `%D' with no type",
                        dname);
          else if (warn_return_type)
            cp_warning ("ANSI C++ forbids declaration `%D' with no type",
                        dname);

          type = integer_type_node;

In this code, the error is always reported unless in_system_header or is_main is true.

I believe the code should be

         if (in_system_header)
            /* Allow it, sigh.  */;
          else if (pedantic && ! is_main)
                            ^^
                             +--------------------------------------------correct
            cp_pedwarn ("ANSI C++ forbids declaration `%D' with no type",
                        dname);
          else if (warn_return_type)
            cp_warning ("ANSI C++ forbids declaration `%D' with no type",
                        dname);

          type = integer_type_node;

In this code, the warnings are only reported if the appropriate command line
flags are set.

Hope this helps,

-Bob Green
Etnus, LLC
rgreen@etnus.com