From 79f925ed078e633914daa2ba9e23b9a827d89264 Mon Sep 17 00:00:00 2001
From: jsm28 <jsm28@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Sun, 4 Dec 2005 23:04:59 +0000
Subject: [PATCH] * c-typeck.c (null_pointer_constant_p): New function.
(build_conditional_expr, build_c_cast, convert_for_assignment,
build_binary_op): Use it.
testsuite:
* gcc.dg/c90-const-expr-5.c, gcc.dg/c99-const-expr-5.c: New tests.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@108022 138bc75d-0d04-0410-961f-82ee72b054a4
---
gcc/ChangeLog | 6 +++
gcc/c-typeck.c | 50 ++++++++++++++++---------
gcc/testsuite/ChangeLog | 4 ++
gcc/testsuite/gcc.dg/c90-const-expr-5.c | 39 +++++++++++++++++++
gcc/testsuite/gcc.dg/c99-const-expr-5.c | 39 +++++++++++++++++++
5 files changed, 120 insertions(+), 18 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/c90-const-expr-5.c
create mode 100644 gcc/testsuite/gcc.dg/c99-const-expr-5.c
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 31ac7608d96f..15da7d4a1421 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2005-12-04 Joseph S. Myers <joseph@codesourcery.com>
+
+ * c-typeck.c (null_pointer_constant_p): New function.
+ (build_conditional_expr, build_c_cast, convert_for_assignment,
+ build_binary_op): Use it.
+
2005-12-04 Joseph S. Myers <joseph@codesourcery.com>
* c-common.c (binary_op_error): Do not allow NOP_EXPR.
diff --git a/gcc/c-typeck.c b/gcc/c-typeck.c
index e4e21dc101d3..36c9bc0702c8 100644
--- a/gcc/c-typeck.c
+++ b/gcc/c-typeck.c
@@ -74,6 +74,7 @@ static int missing_braces_mentioned;
static int require_constant_value;
static int require_constant_elements;
+static bool null_pointer_constant_p (tree);
static tree qualify_type (tree, tree);
static int tagged_types_tu_compatible_p (tree, tree);
static int comp_target_types (tree, tree);
@@ -106,6 +107,23 @@ static int lvalue_or_else (tree, enum lvalue_use);
static int lvalue_p (tree);
static void record_maybe_used_decl (tree);
static int comptypes_internal (tree, tree);
+
+/* Return true if EXP is a null pointer constant, false otherwise. */
+
+static bool
+null_pointer_constant_p (tree expr)
+{
+ /* This should really operate on c_expr structures, but they aren't
+ yet available everywhere required. */
+ tree type = TREE_TYPE (expr);
+ return (TREE_CODE (expr) == INTEGER_CST
+ && !TREE_CONSTANT_OVERFLOW (expr)
+ && integer_zerop (expr)
+ && (INTEGRAL_TYPE_P (type)
+ || (TREE_CODE (type) == POINTER_TYPE
+ && VOID_TYPE_P (TREE_TYPE (type))
+ && TYPE_QUALS (TREE_TYPE (type)) == TYPE_UNQUALIFIED)));
+}
/* This is a cache to hold if two types are compatible or not. */
struct tagged_tu_seen_cache {
@@ -3205,9 +3223,9 @@ build_conditional_expr (tree ifexp, tree op1, tree op2)
{
if (comp_target_types (type1, type2))
result_type = common_pointer_type (type1, type2);
- else if (integer_zerop (orig_op1) && TREE_TYPE (type1) == void_type_node)
+ else if (null_pointer_constant_p (orig_op1))
result_type = qualify_type (type2, type1);
- else if (integer_zerop (orig_op2) && TREE_TYPE (type2) == void_type_node)
+ else if (null_pointer_constant_p (orig_op2))
result_type = qualify_type (type1, type2);
else if (VOID_TYPE_P (TREE_TYPE (type1)))
{
@@ -3233,7 +3251,7 @@ build_conditional_expr (tree ifexp, tree op1, tree op2)
}
else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
{
- if (!integer_zerop (op2))
+ if (!null_pointer_constant_p (orig_op2))
pedwarn ("pointer/integer type mismatch in conditional expression");
else
{
@@ -3243,7 +3261,7 @@ build_conditional_expr (tree ifexp, tree op1, tree op2)
}
else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
{
- if (!integer_zerop (op1))
+ if (!null_pointer_constant_p (orig_op1))
pedwarn ("pointer/integer type mismatch in conditional expression");
else
{
@@ -3481,7 +3499,7 @@ build_c_cast (tree type, tree expr)
&& TREE_CODE (otype) == POINTER_TYPE
&& TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
&& TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
- && !(integer_zerop (value) && TREE_TYPE (otype) == void_type_node))
+ && !null_pointer_constant_p (value))
pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
ovalue = value;
@@ -3834,7 +3852,7 @@ convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
}
/* Can convert integer zero to any pointer type. */
- if (integer_zerop (rhs))
+ if (null_pointer_constant_p (rhs))
{
rhs = null_pointer_node;
break;
@@ -3972,7 +3990,7 @@ convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
&& ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
||
(VOID_TYPE_P (ttr)
- && !integer_zerop (rhs)
+ && !null_pointer_constant_p (rhs)
&& TREE_CODE (ttl) == FUNCTION_TYPE)))
WARN_FOR_ASSIGNMENT (G_("ISO C forbids passing argument %d of "
"%qE between function pointer "
@@ -4062,7 +4080,7 @@ convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
/* An explicit constant 0 can convert to a pointer,
or one that results from arithmetic, even including
a cast to integer type. */
- if (!integer_zerop (rhs))
+ if (!null_pointer_constant_p (rhs))
WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
"pointer from integer without a cast"),
G_("assignment makes pointer from integer "
@@ -7900,14 +7918,14 @@ build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
{
/* op0 != orig_op0 detects the case of something
whose value is 0 but which isn't a valid null ptr const. */
- if (pedantic && (!integer_zerop (op0) || op0 != orig_op0)
+ if (pedantic && !null_pointer_constant_p (orig_op0)
&& TREE_CODE (tt1) == FUNCTION_TYPE)
pedwarn ("ISO C forbids comparison of %<void *%>"
" with function pointer");
}
else if (VOID_TYPE_P (tt1))
{
- if (pedantic && (!integer_zerop (op1) || op1 != orig_op1)
+ if (pedantic && !null_pointer_constant_p (orig_op1)
&& TREE_CODE (tt0) == FUNCTION_TYPE)
pedwarn ("ISO C forbids comparison of %<void *%>"
" with function pointer");
@@ -7920,11 +7938,9 @@ build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
if (result_type == NULL_TREE)
result_type = ptr_type_node;
}
- else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
- && integer_zerop (op1))
+ else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
result_type = type0;
- else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
- && integer_zerop (op0))
+ else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
result_type = type1;
else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
{
@@ -7964,15 +7980,13 @@ build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
pedwarn ("comparison of distinct pointer types lacks a cast");
}
}
- else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
- && integer_zerop (op1))
+ else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
{
result_type = type0;
if (pedantic || extra_warnings)
pedwarn ("ordered comparison of pointer with integer zero");
}
- else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
- && integer_zerop (op0))
+ else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
{
result_type = type1;
if (pedantic)
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 93e36dc12bca..fb0d84d7141a 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2005-12-04 Joseph S. Myers <joseph@codesourcery.com>
+
+ * gcc.dg/c90-const-expr-5.c, gcc.dg/c99-const-expr-5.c: New tests.
+
2005-12-04 Joseph S. Myers <joseph@codesourcery.com>
* gcc.dg/format/cast-1.c: New test.
diff --git a/gcc/testsuite/gcc.dg/c90-const-expr-5.c b/gcc/testsuite/gcc.dg/c90-const-expr-5.c
new file mode 100644
index 000000000000..132932b565a4
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/c90-const-expr-5.c
@@ -0,0 +1,39 @@
+/* Test null pointer constants: typedefs for void should be OK but not
+ qualified void. */
+/* Origin: Joseph Myers <joseph@codesourcery.com> */
+/* { dg-do compile } */
+/* { dg-options "-std=iso9899:1990 -pedantic-errors" } */
+
+typedef void V;
+int *p;
+long *q;
+int j;
+void (*fp)(void);
+
+void
+f (void)
+{
+ /* (V *)0 is a null pointer constant, so the assignment should be
+ diagnosed. */
+ q = (j ? p : (V *)0); /* { dg-error "error: assignment from incompatible pointer type" } */
+ q = (j ? p : (void *)0); /* { dg-error "error: assignment from incompatible pointer type" } */
+ /* And this conversion should be valid. */
+ (void (*)(void))(V *)0;
+ (void (*)(void))(void *)0;
+ /* Pointers to qualified void are not valid null pointer
+ constants. */
+ fp = (const void *)0; /* { dg-error "error: ISO C forbids assignment between function pointer and 'void \\*'" } */
+ fp = (void *)0;
+ fp = (V *)0;
+ fp = 0;
+ fp == 0;
+ 0 == fp;
+ fp == (void *)0;
+ (void *)0 == fp;
+ fp == (V *)0;
+ (V *)0 == fp;
+ fp == (V *)1; /* { dg-error "error: ISO C forbids comparison of 'void \\*' with function pointer" } */
+ (V *)1 == fp; /* { dg-error "error: ISO C forbids comparison of 'void \\*' with function pointer" } */
+ fp == (const void *)0; /* { dg-error "error: ISO C forbids comparison of 'void \\*' with function pointer" } */
+ (const void *)0 == fp; /* { dg-error "error: ISO C forbids comparison of 'void \\*' with function pointer" } */
+}
diff --git a/gcc/testsuite/gcc.dg/c99-const-expr-5.c b/gcc/testsuite/gcc.dg/c99-const-expr-5.c
new file mode 100644
index 000000000000..e7fdf2c644bf
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/c99-const-expr-5.c
@@ -0,0 +1,39 @@
+/* Test null pointer constants: typedefs for void should be OK but not
+ qualified void. */
+/* Origin: Joseph Myers <joseph@codesourcery.com> */
+/* { dg-do compile } */
+/* { dg-options "-std=iso9899:1999 -pedantic-errors" } */
+
+typedef void V;
+int *p;
+long *q;
+int j;
+void (*fp)(void);
+
+void
+f (void)
+{
+ /* (V *)0 is a null pointer constant, so the assignment should be
+ diagnosed. */
+ q = (j ? p : (V *)0); /* { dg-error "error: assignment from incompatible pointer type" } */
+ q = (j ? p : (void *)0); /* { dg-error "error: assignment from incompatible pointer type" } */
+ /* And this conversion should be valid. */
+ (void (*)(void))(V *)0;
+ (void (*)(void))(void *)0;
+ /* Pointers to qualified void are not valid null pointer
+ constants. */
+ fp = (const void *)0; /* { dg-error "error: ISO C forbids assignment between function pointer and 'void \\*'" } */
+ fp = (void *)0;
+ fp = (V *)0;
+ fp = 0;
+ fp == 0;
+ 0 == fp;
+ fp == (void *)0;
+ (void *)0 == fp;
+ fp == (V *)0;
+ (V *)0 == fp;
+ fp == (V *)1; /* { dg-error "error: ISO C forbids comparison of 'void \\*' with function pointer" } */
+ (V *)1 == fp; /* { dg-error "error: ISO C forbids comparison of 'void \\*' with function pointer" } */
+ fp == (const void *)0; /* { dg-error "error: ISO C forbids comparison of 'void \\*' with function pointer" } */
+ (const void *)0 == fp; /* { dg-error "error: ISO C forbids comparison of 'void \\*' with function pointer" } */
+}
--
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