diff options
| -rw-r--r-- | gcc/cp/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/cp/decl.c | 47 | ||||
| -rw-r--r-- | gcc/testsuite/g++.old-deja/g++.other/scope1.C | 12 |
3 files changed, 56 insertions, 9 deletions
diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog index 1c263e5..507edd8 100644 --- a/gcc/cp/ChangeLog +++ b/gcc/cp/ChangeLog @@ -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> * ir.texi (Expressions): Fix typo. diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c index 613c44e..552070b 100644 --- a/gcc/cp/decl.c +++ b/gcc/cp/decl.c @@ -3852,7 +3852,7 @@ pushdecl (x) nesting. */ && !(TREE_CODE (x) == FUNCTION_DECL && !DECL_INITIAL (x)) /* 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. */ && !(TREE_CODE (x) == VAR_DECL && DECL_EXTERNAL (x)) && !DECL_CONTEXT (x)) @@ -3871,20 +3871,40 @@ pushdecl (x) name = DECL_NAME (x); if (name) { -#if 0 - /* Not needed...see below. */ - char *file; - int line; -#endif + int different_binding_level = 0; + if (TREE_CODE (name) == TEMPLATE_ID_EXPR) name = TREE_OPERAND (name, 0); - /* Namespace-scoped variables are not found in the current level. */ - if (TREE_CODE (x) == VAR_DECL && DECL_NAMESPACE_SCOPE_P (x)) + /* In case this decl was explicitly namespace-qualified, look it + 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)); else 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 was an OVERLOAD, look for an overloaded instance that is actually the same as the function we are declaring. (If @@ -3919,7 +3939,16 @@ pushdecl (x) } 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) fatal ("parse errors have confused me too much"); diff --git a/gcc/testsuite/g++.old-deja/g++.other/scope1.C b/gcc/testsuite/g++.old-deja/g++.other/scope1.C new file mode 100644 index 0000000..8b6354c --- /dev/null +++ b/gcc/testsuite/g++.old-deja/g++.other/scope1.C @@ -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); + } +} |