FreeChainXenon/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

re PR middle-end/179 (-Wuninitialized missing warning with &var)

Browse source 
2008-08-21  Manuel Lopez-Ibanez  <manu@gcc.gnu.org>

	PR middle-end/179
	* tree-ssa.c (warn_uninit): Do not warn for variables that can be
	initialized outside the current module.
	(warn_uninitialized_var): Ignore left-hand side when walking the
	trees. Ignore address expressions. Examine VUSE operands in gimple
	statements with a variable declaration on the right-hand side.
testsuite/
	* gcc.dg/uninit-6.c (make_something): Remove XFAIL.
	* gcc.dg/uninit-6-O0.c (make_something): Remove XFAIL.
	* gcc.dg/uninit-B.c (baz): Remove XFAIL.
	* gcc.dg/uninit-B-2.c: New.
	* gcc.dg/uninit-B-O0-2.c: New.
	* gcc.dg/uninit-pr19430-O0.c: New.
	* gcc.dg/uninit-pr19430.c: New.
	* gcc.dg/uninit-pr19430-2.c: New.

From-SVN: r139347
This commit is contained in:
Manuel López-Ibáñez 2008-08-20 22:23:45 +00:00
parent 7735154d75
commit 87fe2bd0e0
11 changed files with 202 additions and 3 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

9
gcc/ChangeLog
View file

@ -1,3 +1,12 @@
2008-08-21 Manuel Lopez-Ibanez <manu@gcc.gnu.org>
PR middle-end/179
* tree-ssa.c (warn_uninit): Do not warn for variables that can be
initialized outside the current module.
(warn_uninitialized_var): Ignore left-hand side when walking the
trees. Ignore address expressions. Examine VUSE operands in gimple
statements with a variable declaration on the right-hand side.
2008-08-20 Richard Sandiford <rdsandiford@googlemail.com>
PR bootstrap/37155

12
gcc/testsuite/ChangeLog
View file

@ -1,3 +1,15 @@
2008-08-21 Manuel Lopez-Ibanez <manu@gcc.gnu.org>
PR middle-end/179
* gcc.dg/uninit-6.c (make_something): Remove XFAIL.
* gcc.dg/uninit-6-O0.c (make_something): Remove XFAIL.
* gcc.dg/uninit-B.c (baz): Remove XFAIL.
* gcc.dg/uninit-B-2.c: New.
* gcc.dg/uninit-B-O0-2.c: New.
* gcc.dg/uninit-pr19430-O0.c: New.
* gcc.dg/uninit-pr19430.c: New.
* gcc.dg/uninit-pr19430-2.c: New.
2008-08-20 Manuel Lopez-Ibanez <manu@gcc.gnu.org>
PR c++/35158

2
gcc/testsuite/gcc.dg/uninit-6-O0.c
View file

@ -39,7 +39,7 @@ make_something(int a, int b, int c)
rv = malloc (sizeof (struct tree));
rv->car = 0;
APPEND(rv, field, INTEGER_T, a); /* { dg-bogus "field" "uninitialized variable warning" { xfail *-*-* } } */
APPEND(rv, field, INTEGER_T, a); /* { dg-bogus "field" "uninitialized variable warning" } */
APPEND(rv, field, PTR_T, b);
APPEND(rv, field, INTEGER_T, c);

2
gcc/testsuite/gcc.dg/uninit-6.c
View file

@ -39,7 +39,7 @@ make_something(int a, int b, int c)
rv = malloc (sizeof (struct tree));
rv->car = 0;
APPEND(rv, field, INTEGER_T, a); /* { dg-bogus "field" "uninitialized variable warning" { xfail *-*-* } } */
APPEND(rv, field, INTEGER_T, a); /* { dg-bogus "field" "uninitialized variable warning" } */
APPEND(rv, field, PTR_T, b);
APPEND(rv, field, INTEGER_T, c);

16
gcc/testsuite/gcc.dg/uninit-B-2.c Normal file
View file

@ -0,0 +1,16 @@
/* Origin: PR c/179 inverse of uninit-B-O0.c, we should not warn. */
/* { dg-do compile } */
/* { dg-options "-O2 -Wuninitialized" } */
extern void foo (int *);
extern void bar (int);
void
baz (void)
{
int i;
foo (&i); /* { dg-bogus "is used uninitialized" "uninit i warning" } */
if (i)
bar (i);
}

16
gcc/testsuite/gcc.dg/uninit-B-O0-2.c Normal file
View file

@ -0,0 +1,16 @@
/* Origin: PR c/179 inverse of uninit-B-O0.c, we should not warn. */
/* { dg-do compile } */
/* { dg-options "-O0 -Wuninitialized" } */
extern void foo (int *);
extern void bar (int);
void
baz (void)
{
int i;
foo (&i); /* { dg-bogus "is used uninitialized" "uninit i warning" } */
if (i)
bar (i);
}

2
gcc/testsuite/gcc.dg/uninit-B.c
View file

@ -9,7 +9,7 @@ void
baz (void)
{
int i;
if (i) /* { dg-warning "uninit" "uninit i warning" { xfail *-*-* } } */
if (i) /* { dg-warning "is used uninitialized" "uninit i warning" } */
bar (i);
foo (&i);
}

18
gcc/testsuite/gcc.dg/uninit-pr19430-2.c Normal file
View file

@ -0,0 +1,18 @@
/* { dg-do compile } */
/* { dg-options "-O -Wuninitialized" } */
int *p, *q;
int foo (int b)
{
int i, j = 0;
int *x;
p = &i;
q = &j;
if (b)
x = p;
else
x = q;
return *x;
}

43
gcc/testsuite/gcc.dg/uninit-pr19430-O0.c Normal file
View file

@ -0,0 +1,43 @@
/* { dg-do compile } */
/* { dg-options "-O0 -Wuninitialized" } */
extern int bar (int);
extern void baz (int *);
int
foo (int i)
{
int j; /* { dg-warning "'j' may be used uninitialized in this function" "uninitialized" { xfail *-*-* } 9 } */
if (bar (i)) {
baz (&j);
} else {
}
return j;
}
int foo2( void ) {
int rc; /* { dg-warning "'rc' is used uninitialized in this function" "uninitialized" { xfail *-*-* } 21 } */
return rc;
*&rc = 0;
}
extern int printf(const char *, ...);
void frob(int *pi);
int main(void)
{
int i;
printf("i = %d\n", i); /* { dg-warning "'i' is used uninitialized in this function" "uninitialized" { xfail *-*-* } 32 } */
frob(&i);
return 0;
}
void foo3(int*);
void bar3(void) {
int x;
if(x) /* { dg-warning "'x' is used uninitialized in this function" "uninitialized" { xfail *-*-* } 41 } */
foo3(&x);
}

43
gcc/testsuite/gcc.dg/uninit-pr19430.c Normal file
View file

@ -0,0 +1,43 @@
/* { dg-do compile } */
/* { dg-options "-O -Wuninitialized" } */
extern int bar (int);
extern void baz (int *);
int
foo (int i)
{
int j; /* { dg-warning "'j' may be used uninitialized in this function" "uninitialized" { xfail *-*-* } 8 } */
if (bar (i)) {
baz (&j);
} else {
}
return j;
}
int foo2( void ) {
int rc; /* { dg-warning "'rc' is used uninitialized in this function" } */
return rc;
*&rc = 0;
}
extern int printf(const char *, ...);
void frob(int *pi);
int main(void)
{
int i;
printf("i = %d\n", i); /* { dg-warning "'i' is used uninitialized in this function" } */
frob(&i);
return 0;
}
void foo3(int*);
void bar3(void) {
int x;
if(x) /* { dg-warning "'x' is used uninitialized in this function" "uninitialized" } */
foo3(&x);
}

42
gcc/tree-ssa.c
View file

@ -1411,6 +1411,10 @@ warn_uninit (tree t, const char *gmsgid, void *data)
if (TREE_NO_WARNING (var))
return;
/* Do not warn if it can be initialized outside this module. */
if (is_global_var (var))
return;
location = (context != NULL && gimple_has_location (context))
? gimple_location (context)
: DECL_SOURCE_LOCATION (var);
@ -1443,8 +1447,46 @@ warn_uninitialized_var (tree *tp, int *walk_subtrees, void *data_)
struct walk_data *data = (struct walk_data *) wi->info;
tree t = *tp;
/* We do not care about LHS. */
if (wi->is_lhs)
return NULL_TREE;
switch (TREE_CODE (t))
{
case ADDR_EXPR:
/* Taking the address of an uninitialized variable does not
count as using it. */
*walk_subtrees = 0;
break;
case VAR_DECL:
{
/* A VAR_DECL in the RHS of a gimple statement may mean that
this variable is loaded from memory. */
use_operand_p vuse;
tree op;
/* If there is not gimple stmt,
or alias information has not been computed,
then we cannot check VUSE ops. */
if (data->stmt == NULL
|| !gimple_aliases_computed_p (cfun))
return NULL_TREE;
vuse = SINGLE_SSA_USE_OPERAND (data->stmt, SSA_OP_VUSE);
if (vuse == NULL_USE_OPERAND_P)
return NULL_TREE;
op = USE_FROM_PTR (vuse);
if (t != SSA_NAME_VAR (op)
|| !SSA_NAME_IS_DEFAULT_DEF (op))
return NULL_TREE;
/* If this is a VUSE of t and it is the default definition,
then warn about op. */
t = op;
/* Fall through into SSA_NAME. */
}
case SSA_NAME:
/* We only do data flow with SSA_NAMEs, so that's all we
can warn about. */