re PR c++/19628 (g++ no longer accepts __builtin_constant_p in constant-expressions)

PR c++/19628

* cp-tree.h (builtin_valid_in_constant_expr_p): Declare.
* parser.c (cp_parser_postfix_expression): Accept function call in constant expression if builtin_valid_in_constant_expr_p is true for that function.
* pt.c (value_dependent_expression_p): Handle CALL_EXPRs properly.
* semantics.c (finish_id_expression): Accept function call in constant expression if builtin_valid_in_constant_expr_p is true for that function.
* tree.c (builtin_valid_in_constant_expr_p): New.

* g++/ext/builtin7.C: New.
* g++/ext/builtin8.C: New.

From-SVN: r94635
This commit is contained in:
Matt Austern 2005-02-03 00:02:10 +00:00 committed by Matt Austern
parent 89d12f5d49
commit 100d337a9d
9 changed files with 98 additions and 3 deletions

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@ -1,3 +1,16 @@
2005-02-02 Matt Austern <austern@apple.com>
PR c++/19628
* cp-tree.h (builtin_valid_in_constant_expr_p): Declare.
* parser.c (cp_parser_postfix_expression): Accept function call in
constant expression if builtin_valid_in_constant_expr_p is true
for that function.
* pt.c (value_dependent_expression_p): Handle CALL_EXPRs properly.
* semantics.c (finish_id_expression): Accept function call in constant
expression if builtin_valid_in_constant_expr_p is true for that
function.
* tree.c (builtin_valid_in_constant_expr_p): New.
2005-02-02 Volker Reichelt <reichelt@igpm.rwth-aachen.de>
PR c++/17413

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@ -4205,6 +4205,7 @@ extern tree copy_binfo (tree, tree, tree,
tree *, int);
extern int member_p (tree);
extern cp_lvalue_kind real_lvalue_p (tree);
extern bool builtin_valid_in_constant_expr_p (tree);
extern tree build_min (enum tree_code, tree, ...);
extern tree build_min_nt (enum tree_code, ...);
extern tree build_min_non_dep (enum tree_code, tree, ...);

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@ -4037,8 +4037,9 @@ cp_parser_postfix_expression (cp_parser *parser, bool address_p, bool cast_p)
/* Function calls are not permitted in
constant-expressions. */
if (cp_parser_non_integral_constant_expression (parser,
"a function call"))
if (! builtin_valid_in_constant_expr_p (postfix_expression)
&& cp_parser_non_integral_constant_expression (parser,
"a function call"))
{
postfix_expression = error_mark_node;
break;

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@ -12020,6 +12020,36 @@ value_dependent_expression_p (tree expression)
if (TREE_CODE (expression) == COMPONENT_REF)
return (value_dependent_expression_p (TREE_OPERAND (expression, 0))
|| value_dependent_expression_p (TREE_OPERAND (expression, 1)));
/* A CALL_EXPR is value-dependent if any argument is
value-dependent. Why do we have to handle CALL_EXPRs in this
function at all? First, some function calls, those for which
value_dependent_expression_p is true, man appear in constant
expressions. Second, there appear to be bugs which result in
other CALL_EXPRs reaching this point. */
if (TREE_CODE (expression) == CALL_EXPR)
{
tree function = TREE_OPERAND (expression, 0);
tree args = TREE_OPERAND (expression, 1);
if (value_dependent_expression_p (function))
return true;
else if (! args)
return false;
else if (TREE_CODE (args) == TREE_LIST)
{
do
{
if (value_dependent_expression_p (TREE_VALUE (args)))
return true;
args = TREE_CHAIN (args);
}
while (args);
return false;
}
else
return value_dependent_expression_p (args);
}
/* A constant expression is value-dependent if any subexpression is
value-dependent. */
if (EXPR_P (expression))

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@ -2663,7 +2663,8 @@ finish_id_expression (tree id_expression,
expression. Enumerators and template parameters have already
been handled above. */
if (integral_constant_expression_p
&& !DECL_INTEGRAL_CONSTANT_VAR_P (decl))
&& ! DECL_INTEGRAL_CONSTANT_VAR_P (decl)
&& ! builtin_valid_in_constant_expr_p (decl))
{
if (!allow_non_integral_constant_expression_p)
{

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@ -215,6 +215,19 @@ lvalue_p (tree ref)
(lvalue_p_1 (ref, /*class rvalue ok*/ 1) != clk_none);
}
/* Test whether DECL is a builtin that may appear in a
constant-expression. */
bool
builtin_valid_in_constant_expr_p (tree decl)
{
/* At present BUILT_IN_CONSTANT_P is the only builtin we're allowing
in constant-expressions. We may want to add other builtins later. */
return TREE_CODE (decl) == FUNCTION_DECL
&& DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
&& DECL_FUNCTION_CODE (decl) == BUILT_IN_CONSTANT_P;
}
/* Build a TARGET_EXPR, initializing the DECL with the VALUE. */
static tree

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@ -1,3 +1,9 @@
2005-02-02 Matt Austern <austern@apple.com>
PR c++/19628
* g++/ext/builtin7.C: New.
* g++/ext/builtin8.C: New.
2005-02-02 Joseph S. Myers <joseph@codesourcery.com>
PR c/18502

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@ -0,0 +1,14 @@
// PR c++/19628
// Verify that __builtin_constant_p may appear in a constant-expression.
// { dg-do run }
int main()
{
switch (3) {
case (__builtin_constant_p(7) ? 3 : 8):
return 0;
default:
return 1;
}
}

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@ -0,0 +1,16 @@
// PR c++/19628
// Verify that __builtin_constant_p may appear in a constant-expression.
// { dg-do compile }
template <int I>
int f(int x[__builtin_constant_p(I)])
{
return x[0];
}
int g()
{
int a[1] = { 7 };
return f<32>(a);
}