binutils-gdb/gdb/testsuite/gdb.base/vla-sideeffect.c
Sanimir Agovic 5ecaaa66e0 vla: evaluate operand of sizeof if its type is a vla
The c99 standard in "6.5.3.4 The sizeof operator" states:

 If the type of the operand is a variable length array type, the operand
 is evaluated;[...]

This patch mirrors the following c99 semantic in gdb:

 1| int vla[n][m];
 2| int i = 1;
 3| sizeof(vla[i++][0]); // No sideffect
 4| assert (i == 1);
 5| sizeof(vla[i++]);    // With sideffect
 6| assert (i == 2);

Note: ptype/whatis still do not allow any sideeffects.

This patch was motivated by:

  https://sourceware.org/ml/gdb-patches/2014-01/msg00732.html

gdb/ChangeLog:

	* eval.c (evaluate_subexp_for_sizeof): Add enum noside argument.
	(evaluate_subexp_standard): Pass noside argument.
	(evaluate_subexp_for_sizeof) <BINOP_SUBSCRIPT>: Handle subscript case
	if noside equals EVAL_NORMAL. If the subscript yields a vla type
	re-evaluate subscript operation with EVAL_NORMAL to enable sideffects.
	* gdbtypes.c (resolve_dynamic_bounds): Mark bound as evaluated.
	* gdbtypes.h (enum range_flags): Add RANGE_EVALUATED case.

testsuite/ChangeLog:

	* gdb.base/vla-sideeffect.c: New file.
	* gdb.base/vla-sideeffect.exp: New file.
2014-04-14 09:21:46 -07:00

43 lines
1.1 KiB
C

/* This testcase is part of GDB, the GNU debugger.
Copyright 2014 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#include <stddef.h>
#define SIZE 10
int
main (void)
{
int n = SIZE;
int i = 0;
int j = 0;
int vla2[SIZE][n];
int vla1[n];
for (i = 0; i < n; i++)
vla1[i] = (i * 2) + n;
for (i = 0; i < SIZE; i++)
for (j = 0; j < n; j++)
vla2[i][j] = (i + j) + n;
i = 0;
j = 0;
return 0; /* vla-filled */
}