commit af8514f2c47162f32f56d0ee3f18e9040d756b1f
Author: Jason Merrill <jason@redhat.com>
Date: Mon Jul 11 09:38:11 2011 -0400
PR c++/44609
* cp-tree.h (struct tinst_level): Add errors field.
* pt.c (neglectable_inst_p, limit_bad_template_recurson): New.
(push_tinst_level): Don't start another decl in that case.
(reopen_tinst_level): Adjust errors field.
* decl2.c (cp_write_global_declarations): Don't complain about
undefined inline if its template was defined.
* mangle.c (mangle_decl_string): Handle failure from push_tinst_level.
@@ -4679,6 +4679,9 @@ struct GTY((chain_next ("%h.next"))) tinst_level {
/* The location where the template is instantiated. */
location_t locus;
+ /* errorcount+sorrycount when we pushed this level. */
+ int errors;
+
/* True if the location is in a system header. */
bool in_system_header_p;
};
@@ -3950,10 +3950,10 @@ cp_write_global_declarations (void)
#pragma interface, etc.) we decided not to emit the
definition here. */
&& !DECL_INITIAL (decl)
- /* An explicit instantiation can be used to specify
- that the body is in another unit. It will have
- already verified there was a definition. */
- && !DECL_EXPLICIT_INSTANTIATION (decl))
+ /* Don't complain if the template was defined. */
+ && !(DECL_TEMPLATE_INSTANTIATION (decl)
+ && DECL_INITIAL (DECL_TEMPLATE_RESULT
+ (template_for_substitution (decl)))))
{
warning (0, "inline function %q+D used but never defined", decl);
/* Avoid a duplicate warning from check_global_declaration_1. */
@@ -3106,11 +3106,11 @@ mangle_decl_string (const tree decl)
if (DECL_LANG_SPECIFIC (decl) && DECL_USE_TEMPLATE (decl))
{
struct tinst_level *tl = current_instantiation ();
- if (!tl || tl->decl != decl)
+ if ((!tl || tl->decl != decl)
+ && push_tinst_level (decl))
{
template_p = true;
saved_fn = current_function_decl;
- push_tinst_level (decl);
current_function_decl = NULL_TREE;
}
}
@@ -7499,6 +7499,36 @@ uses_template_parms_level (tree t, int level)
/*include_nondeduced_p=*/true);
}
+/* Returns TRUE iff INST is an instantiation we don't need to do in an
+ ill-formed translation unit, i.e. a variable or function that isn't
+ usable in a constant expression. */
+
+static inline bool
+neglectable_inst_p (tree d)
+{
+ return (DECL_P (d)
+ && !(TREE_CODE (d) == FUNCTION_DECL ? DECL_DECLARED_CONSTEXPR_P (d)
+ : decl_maybe_constant_var_p (d)));
+}
+
+/* Returns TRUE iff we should refuse to instantiate DECL because it's
+ neglectable and instantiated from within an erroneous instantiation. */
+
+static bool
+limit_bad_template_recurson (tree decl)
+{
+ struct tinst_level *lev = current_tinst_level;
+ int errs = errorcount + sorrycount;
+ if (lev == NULL || errs == 0 || !neglectable_inst_p (decl))
+ return false;
+
+ for (; lev; lev = lev->next)
+ if (neglectable_inst_p (lev->decl))
+ break;
+
+ return (lev && errs > lev->errors);
+}
+
static int tinst_depth;
extern int max_tinst_depth;
#ifdef GATHER_STATISTICS
@@ -7532,9 +7562,16 @@ push_tinst_level (tree d)
return 0;
}
+ /* If the current instantiation caused problems, don't let it instantiate
+ anything else. Do allow deduction substitution and decls usable in
+ constant expressions. */
+ if (limit_bad_template_recurson (d))
+ return 0;
+
new_level = ggc_alloc_tinst_level ();
new_level->decl = d;
new_level->locus = input_location;
+ new_level->errors = errorcount+sorrycount;
new_level->in_system_header_p = in_system_header;
new_level->next = current_tinst_level;
current_tinst_level = new_level;
@@ -7578,6 +7615,8 @@ reopen_tinst_level (struct tinst_level *level)
current_tinst_level = level;
pop_tinst_level ();
+ if (current_tinst_level)
+ current_tinst_level->errors = errorcount+sorrycount;
return level->decl;
}
new file mode 100644
@@ -0,0 +1,14 @@
+// PR c++/44609
+// { dg-options -ftemplate-depth=10 }
+
+template<int N>
+void f()
+{
+ 0 = 0; // { dg-error "lvalue required" }
+ f<N+1>(); // { dg-bogus "instantiation depth" }
+}
+
+int main()
+{
+ f<0>();
+}
commit 6d77d383471e8be7119cb001f985be1ea9ce97d9
Author: Jason Merrill <jason@redhat.com>
Date: Mon Jul 11 11:04:41 2011 -0400
* decl2.c (decl_constant_var_p): Use decl_maybe_constant_var_p.
@@ -3574,26 +3574,16 @@ decl_defined_p (tree decl)
bool
decl_constant_var_p (tree decl)
{
- bool ret;
- tree type = TREE_TYPE (decl);
- if (TREE_CODE (decl) != VAR_DECL)
+ if (!decl_maybe_constant_var_p (decl))
return false;
- if (DECL_DECLARED_CONSTEXPR_P (decl)
- || (CP_TYPE_CONST_NON_VOLATILE_P (type)
- && INTEGRAL_OR_ENUMERATION_TYPE_P (type)))
- {
- /* We don't know if a template static data member is initialized with
- a constant expression until we instantiate its initializer. Even
- in the case of a constexpr variable, we can't treat it as a
- constant until its initializer is complete in case it's used in
- its own initializer. */
- mark_used (decl);
- ret = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl);
- }
- else
- ret = false;
- return ret;
+ /* We don't know if a template static data member is initialized with
+ a constant expression until we instantiate its initializer. Even
+ in the case of a constexpr variable, we can't treat it as a
+ constant until its initializer is complete in case it's used in
+ its own initializer. */
+ mark_used (decl);
+ return DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl);
}
/* Returns true if DECL could be a symbolic constant variable, depending on