[binutils-gdb] Handle alignof and _Alignof

[sergiodj+buildbot@sergiodj.net]

*** TEST RESULTS FOR COMMIT 007e1530347330d4dbba387c4e35aae05bc06498 ***

Author: Tom Tromey <tom@tromey.com>
Branch: master
Commit: 007e1530347330d4dbba387c4e35aae05bc06498

Handle alignof and _Alignof

This adds alignof and _Alignof to the C/C++ expression parser, and
adds new tests to test the features.  The tests are written to try to
ensure that gdb's knowledge of alignment rules stays in sync with the
compiler's.

2018-04-30  Tom Tromey  <tom@tromey.com>

	PR exp/17095:
	* NEWS: Update.
	* std-operator.def (UNOP_ALIGNOF): New operator.
	* expprint.c (dump_subexp_body_standard) <case UNOP_ALIGNOF>:
	New.
	* eval.c (evaluate_subexp_standard) <case UNOP_ALIGNOF>: New.
	* c-lang.c (c_op_print_tab): Add alignof.
	* c-exp.y (ALIGNOF): New token.
	(exp): Add "ALIGNOF" production.
	(ident_tokens): Add _Alignof and alignof.

2018-04-30  Tom Tromey  <tom@tromey.com>

	PR exp/17095:
	* gdb.dwarf2/dw2-align.exp: New file.
	* gdb.cp/align.exp: New file.
	* gdb.base/align.exp: New file.
	* lib/gdb.exp (gdb_int128_helper): New proc.
	(has_int128_c, has_int128_cxx): New caching procs.