* c-tree.h (enum c_storage_class): New.
	(struct c_declspecs): Add storage_class, inline_p and thread_p.
	* c-decl.c (shadow_tag_warned): Give errors for "inline" in empty
	declarations and "auto" or "register" in file scope empty
	declarations.  Give more specific warnings for other cases of
	storage class specifiers in empty declarations.
	(grokdeclarator): Update for new structures.  Don't check for
	multiple storage classes.  Diagnose file-scope "register" if
	pedantic.
	(build_null_declspecs): Update.
	(declspecs_add_scspec): Update.  Diagnose multiple storage class
	specifiers and invalid uses of "__thread".

testsuite:
	* gcc.dg/declspec-4.c, gcc.dg/declspec-5.c, gcc.dg/declspec-6.c,
	gcc.dg/tls/diag-2.c: Update expected messages.
	* gcc.dg/991209-1.c: Specify compilation options.  Update expected
	messages.
	* gcc.dg/pr14289-2.c, gcc.dg/pr14289-3.c: Remove.
	* gcc.dg/declspec-7.c, gcc.dg/declspec-8.c, gcc.dg/declspec-9.c,
	gcc.dg/declspec-10.c, gcc.dg/declspec-11.c, gcc.dg/tls/diag-4.c,
	gcc.dg/tls/diag-5.c: New tests.

From-SVN: r87374