re PR sanitizer/80800 (UBSAN: yet another false positive)

PR sanitizer/80800
	* fold-const.c (extract_muldiv_1) <case TRUNC_DIV_EXPR>: Add
	TYPE_OVERFLOW_WRAPS checks.

	* c-c++-common/ubsan/pr80800.c: New test.
	* c-c++-common/Wduplicated-branches-1.c: Adjust an expression.

From-SVN: r248291
This commit is contained in:
Marek Polacek 2017-05-19 15:30:54 +00:00 committed by Marek Polacek
parent ff50231797
commit 33f8c0a14d
5 changed files with 40 additions and 1 deletions

View file

@ -1,3 +1,9 @@
2017-05-19 Marek Polacek <polacek@redhat.com>
PR sanitizer/80800
* fold-const.c (extract_muldiv_1) <case TRUNC_DIV_EXPR>: Add
TYPE_OVERFLOW_WRAPS checks.
2017-05-19 Thomas Schwinge <thomas@codesourcery.com>
* tree-core.h (enum omp_clause_default_kind): Add

View file

@ -6281,11 +6281,13 @@ extract_muldiv_1 (tree t, tree c, enum tree_code code, tree wide_type,
new operation. Likewise for the RHS from a MULT_EXPR. Otherwise,
do something only if the second operand is a constant. */
if (same_p
&& TYPE_OVERFLOW_WRAPS (ctype)
&& (t1 = extract_muldiv (op0, c, code, wide_type,
strict_overflow_p)) != 0)
return fold_build2 (tcode, ctype, fold_convert (ctype, t1),
fold_convert (ctype, op1));
else if (tcode == MULT_EXPR && code == MULT_EXPR
&& TYPE_OVERFLOW_WRAPS (ctype)
&& (t1 = extract_muldiv (op1, c, code, wide_type,
strict_overflow_p)) != 0)
return fold_build2 (tcode, ctype, fold_convert (ctype, op0),

View file

@ -1,3 +1,9 @@
2017-05-19 Marek Polacek <polacek@redhat.com>
PR sanitizer/80800
* c-c++-common/ubsan/pr80800.c: New test.
* c-c++-common/Wduplicated-branches-1.c: Adjust an expression.
2017-05-19 Thomas Schwinge <thomas@codesourcery.com>
* c-c++-common/goacc/default-1.c: Update.

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@ -89,7 +89,7 @@ f (int i, int *p)
if (i == 8) /* { dg-warning "this condition has identical branches" } */
return i * 8 * i * 8;
else
return 8 * i * 8 * i;
return i * 8 * i * 8;
if (i == 9) /* { dg-warning "this condition has identical branches" } */

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@ -0,0 +1,25 @@
/* PR sanitizer/80800 */
/* { dg-do run } */
/* { dg-options "-fsanitize=undefined -fsanitize-undefined-trap-on-error" } */
int n = 20000;
int z = 0;
int
fn1 (void)
{
return (n * 10000 * z) * 50;
}
int
fn2 (void)
{
return (10000 * n * z) * 50;
}
int
main ()
{
fn1 ();
fn2 ();
}