Hi!
We incorrectly accept some invalid declare variant cases as if declare
variant wasn't there, in particular if a function template has some dependent
arguments and variant name lookup fails, because that is during
fn_type_unification with complain=tf_none, it just sets it to error_mark_node
and doesn't complain further, because it doesn't know the substitution failed
(we don't return error_mark_node from tsubst_attribute, just create TREE_LIST
with error_mark_node TREE_PURPOSE).
The following patch fixes it by returning error_mark_node in that case, then
fn_type_unification caller can see it failed and can redo it with explain_p
so that errors are reported.
Bootstrapped/regtested on x86_64-linux and i686-linux, committed to trunk.
2024-11-01 Jakub Jelinek <ja...@redhat.com>
* pt.cc (tsubst_attribute): For "omp declare variant base" attribute
if varid is error_mark_node, set val to error_mark_node rather than
creating a TREE_LIST with error_mark_node TREE_PURPOSE.
* g++.dg/gomp/declare-variant-10.C: New test.
--- gcc/cp/pt.cc.jj 2024-10-25 10:00:29.431768386 +0200
+++ gcc/cp/pt.cc 2024-10-31 10:57:05.855001910 +0100
@@ -12163,7 +12163,10 @@ tsubst_attribute (tree t, tree *decl_p,
}
OMP_TSS_TRAIT_SELECTORS (tss) = nreverse (selectors);
}
- val = tree_cons (varid, ctx, chain);
+ if (varid == error_mark_node)
+ val = error_mark_node;
+ else
+ val = tree_cons (varid, ctx, chain);
}
/* If the first attribute argument is an identifier, don't
pass it through tsubst. Attributes like mode, format,
--- gcc/testsuite/g++.dg/gomp/declare-variant-10.C.jj 2024-10-31
11:21:13.962820634 +0100
+++ gcc/testsuite/g++.dg/gomp/declare-variant-10.C 2024-10-31
11:26:59.651011406 +0100
@@ -0,0 +1,56 @@
+// { dg-do compile }
+
+#pragma omp declare variant (f1) match(user={condition(1)}) // { dg-error
"'f1' was not declared in this scope; did you mean 'f2'\\\?" }
+void
+f2 (int)
+{
+}
+
+void f3 (int);
+
+#pragma omp declare variant (f3) match(user={condition(1)}) // { dg-error
"variant 'void f3\\\(int\\\)' and base 'void f4\\\(long int\\\)' have
incompatible types" }
+void
+f4 (long)
+{
+}
+
+#pragma omp declare variant (f5) match(user={condition(1)}) // { dg-error
"there are no arguments to 'f5' that depend on a template parameter, so a
declaration of 'f5' must be available" }
+template <int N>
+void
+f6 (int)
+{
+}
+
+template <int N>
+void f7 (int);
+
+#pragma omp declare variant (f7) match(user={condition(1)}) // { dg-error
"no matching function for call to 'f7\\\(long int\\\)'" }
+template <int N>
+void
+f8 (long)
+{
+}
+
+#pragma omp declare variant (f9) match(user={condition(1)})
+template <typename T>
+void
+f10 (T) // {
dg-error "'f9' was not declared in this scope; did you mean 'f8'\\\?" }
+{
+}
+
+template <typename T>
+void f11 (T, int);
+
+#pragma omp declare variant (f11) match(user={condition(1)}) // { dg-error
"variant 'void f11\\\(T, int\\\) \\\[with T = int\\\]' and base 'void f12\\\(T,
long int\\\) \\\[with T = int\\\]' have incompatible types" }
+template <typename T>
+void
+f12 (T, long)
+{
+}
+
+void
+test ()
+{
+ f10 (0); // { dg-error
"no matching function for call to 'f10\\\(int\\\)'" }
+ f12 (0, 0L);
+}
Jakub
