gcc:
2017-10-06  Bernd Edlinger  <bernd.edlinger@hotmail.de>

	* doc/invoke.texi: Document -Wcast-function-type.
	* recog.h (stored_funcptr): Change signature.
	* tree-dump.c (dump_node): Avoid warning.
	* typed-splay-tree.h (typed_splay_tree): Avoid warning.

libcpp:
2017-10-06  Bernd Edlinger  <bernd.edlinger@hotmail.de>

	* internal.h (maybe_print_line): Change signature.
	
c-family:
2017-10-06  Bernd Edlinger  <bernd.edlinger@hotmail.de>

	* c.opt (Wcast-function-type): New warning option.
	* c-lex.c (get_fileinfo): Avoid warning.
	* c-ppoutput.c (scan_translation_unit_directives_only): Remove cast.

c:
2017-10-06  Bernd Edlinger  <bernd.edlinger@hotmail.de>

	* c-typeck.c (c_safe_arg_type_equiv_p,
	c_safe_function_type_cast_p): New function.
	(build_c_cast): Implement -Wcast-function-type.

cp:
2017-10-06  Bernd Edlinger  <bernd.edlinger@hotmail.de>

	* decl2.c (start_static_storage_duration_function): Avoid warning.
	* typeck.c (cxx_safe_arg_type_equiv_p,
	cxx_safe_function_type_cast_p): New function.
	(build_reinterpret_cast_1): Implement -Wcast-function-type.

testsuite:
2017-10-06  Bernd Edlinger  <bernd.edlinger@hotmail.de>

	* c-c++-common/Wcast-function-type.c: New test.
	* g++.dg/Wcast-function-type.C: New test.