OpenE2K/gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

decl.c (pushdecl): Matching decls for local externs are found in the current level.

Browse Source 
* decl.c (pushdecl): Matching decls for local externs are found in
        the current level.  Propagate linkage information from previous
        declarations.

From-SVN: r36011
This commit is contained in:
Jason Merrill 2000-08-27 21:16:08 -04:00 committed by Jason Merrill
parent bbfbf340fc
commit 94dfccd136
3 changed files with 56 additions and 9 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
gcc/cp/ChangeLog
View File

@ -1,3 +1,9 @@
2000-08-27 Jason Merrill <jason@redhat.com>
* decl.c (pushdecl): Matching decls for local externs are found in
the current level. Propagate linkage information from previous
declarations.
2000-08-26 Gabriel Dos Reis <gdr@codesourcery.com> 2000-08-26 Gabriel Dos Reis <gdr@codesourcery.com>
* ir.texi (Expressions): Fix typo. * ir.texi (Expressions): Fix typo.

47
gcc/cp/decl.c
View File

@ -3852,7 +3852,7 @@ pushdecl (x)
nesting. */ nesting. */
&& !(TREE_CODE (x) == FUNCTION_DECL && !DECL_INITIAL (x)) && !(TREE_CODE (x) == FUNCTION_DECL && !DECL_INITIAL (x))
/* A local declaration for an `extern' variable is in the /* A local declaration for an `extern' variable is in the
scoped of the current namespace, not the current scope of the current namespace, not the current
function. */ function. */
&& !(TREE_CODE (x) == VAR_DECL && DECL_EXTERNAL (x)) && !(TREE_CODE (x) == VAR_DECL && DECL_EXTERNAL (x))
&& !DECL_CONTEXT (x)) && !DECL_CONTEXT (x))
@ -3871,20 +3871,40 @@ pushdecl (x)
name = DECL_NAME (x); name = DECL_NAME (x);
if (name) if (name)
{ {
#if 0 int different_binding_level = 0;
/* Not needed...see below. */
char *file;
int line;
#endif
if (TREE_CODE (name) == TEMPLATE_ID_EXPR) if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
name = TREE_OPERAND (name, 0); name = TREE_OPERAND (name, 0);
/* Namespace-scoped variables are not found in the current level. */ /* In case this decl was explicitly namespace-qualified, look it
if (TREE_CODE (x) == VAR_DECL && DECL_NAMESPACE_SCOPE_P (x)) up in its namespace context. */
if (TREE_CODE (x) == VAR_DECL && DECL_NAMESPACE_SCOPE_P (x)
&& namespace_bindings_p ())
t = namespace_binding (name, DECL_CONTEXT (x)); t = namespace_binding (name, DECL_CONTEXT (x));
else else
t = lookup_name_current_level (name); t = lookup_name_current_level (name);
/* [basic.link] If there is a visible declaration of an entity
with linkage having the same name and type, ignoring entities
declared outside the innermost enclosing namespace scope, the
block scope declaration declares that same entity and
receives the linkage of the previous declaration. */
if (! t && current_function_decl && x != current_function_decl
&& (TREE_CODE (x) == FUNCTION_DECL || TREE_CODE (x) == VAR_DECL)
&& DECL_EXTERNAL (x))
{
/* Look in block scope. */
t = IDENTIFIER_VALUE (name);
/* Or in the innermost namespace. */
if (! t)
t = namespace_binding (name, DECL_CONTEXT (x));
/* Does it have linkage? */
if (t && ! (TREE_STATIC (t) || DECL_EXTERNAL (t)))
t = NULL_TREE;
if (t)
different_binding_level = 1;
}
/* If we are declaring a function, and the result of name-lookup /* If we are declaring a function, and the result of name-lookup
was an OVERLOAD, look for an overloaded instance that is was an OVERLOAD, look for an overloaded instance that is
actually the same as the function we are declaring. (If actually the same as the function we are declaring. (If
@ -3919,7 +3939,16 @@ pushdecl (x)
} }
else if (t != NULL_TREE) else if (t != NULL_TREE)
{ {
if (TREE_CODE (t) == PARM_DECL) if (different_binding_level)
{
if (decls_match (x, t))
/* The standard only says that the local extern
inherits linkage from the previous decl; in
particular, default args are not shared. It would
be nice to propagate inlining info, though. FIXME. */
TREE_PUBLIC (x) = TREE_PUBLIC (t);
}
else if (TREE_CODE (t) == PARM_DECL)
{ {
if (DECL_CONTEXT (t) == NULL_TREE) if (DECL_CONTEXT (t) == NULL_TREE)
fatal ("parse errors have confused me too much"); fatal ("parse errors have confused me too much");

12
gcc/testsuite/g++.old-deja/g++.other/scope1.C Normal file
View File

@ -0,0 +1,12 @@
// Testcase for proper scoping of local externs.
int x = 1;
int main()
{
int x = 2;
{
extern int x;
return (x != 1);
}
}