tree.h (enum tree_index): New member `TI_MAIN_IDENTIFIER'.

	* tree.h (enum tree_index): New member `TI_MAIN_IDENTIFIER'.
	(MAIN_NAME_P, main_identifier_node): New macros.
	* c-common.c (c_common_nodes_and_builtins): Init main_identifier_node.
	* c-decl.c (start_decl, grokdeclarator, start_function,
	store_parm_decls, finish_function): Use MAIN_NAME_P.
	* config/avr/avr.c (function_prologue, function_epilogue): Likewise.
	* config/i386/cygwin.h (SUBTARGET_PROLOGUE): Likewise.
	* config/i386/win32.h (SUBTARGET_PROLOGUE): Likewise.
	* config/pdp11/pdp11.c (output_function_prologue): Likewise.

From-SVN: r35945