Normally we check for incomplete type in start_decl, but that obviously
doesn't work for auto variables. Thanks to Pokechu22 for the analysis and
testcases:
"When cp_finish_decl calls cp_apply_type_quals_to_decl on a const auto or
constexpr auto variable, the type might not be complete the first time
(this happened when auto deduces to an initializer_list).
cp_apply_type_quals_to_decl removes the const qualifier if the type is
not complete, which is appropriate for grokdeclarator, on the assumption
that the type will be complete when called by cp_finish_decl."
Tested x86_64-pc-linux-gnu, applying to trunk.
PR c++/80351
gcc/cp/ChangeLog:
* decl.cc (cp_finish_decl): Check completeness of deduced type.
gcc/testsuite/ChangeLog:
* g++.dg/cpp0x/constexpr-77482.C: Adjust message.
* g++.dg/cpp1y/auto-fn27.C: Likewise.
* g++.dg/cpp1y/lambda-generic-variadic22.C: Likewise.
* g++.dg/cpp1z/decomp54.C: Likewise.
* g++.dg/cpp0x/initlist-const1.C: New test.
* g++.dg/warn/Wunused-var-37.C: New test.
* g++.dg/warn/Wunused-var-38.C: New test.
* g++.dg/warn/Wunused-var-39.C: New test.
---
gcc/cp/decl.cc | 11 ++++
gcc/testsuite/g++.dg/cpp0x/constexpr-77482.C | 2 +-
gcc/testsuite/g++.dg/cpp0x/initlist-const1.C | 7 ++
gcc/testsuite/g++.dg/cpp1y/auto-fn27.C | 2 +-
.../g++.dg/cpp1y/lambda-generic-variadic22.C | 2 +-
gcc/testsuite/g++.dg/cpp1z/decomp54.C | 4 +-
gcc/testsuite/g++.dg/warn/Wunused-var-37.C | 64 +++++++++++++++++++
gcc/testsuite/g++.dg/warn/Wunused-var-38.C | 16 +++++
gcc/testsuite/g++.dg/warn/Wunused-var-39.C | 16 +++++
9 files changed, 119 insertions(+), 5 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/cpp0x/initlist-const1.C
create mode 100644 gcc/testsuite/g++.dg/warn/Wunused-var-37.C
create mode 100644 gcc/testsuite/g++.dg/warn/Wunused-var-38.C
create mode 100644 gcc/testsuite/g++.dg/warn/Wunused-var-39.C
base-commit: 4a8b45e8bc8246bd141dad65f571a3e0cc499c6b
@@ -8129,6 +8129,17 @@ cp_finish_decl (tree decl, tree init, bool init_const_expr_p,
TREE_TYPE (decl) = error_mark_node;
return;
}
+ /* As in start_decl_1, complete so TREE_READONLY is set properly. */
+ if (!processing_template_decl
+ && !type_uses_auto (type)
+ && !COMPLETE_TYPE_P (complete_type (type)))
+ {
+ error_at (location_of (decl),
+ "deduced type %qT for %qD is incomplete", type, decl);
+ cxx_incomplete_type_inform (type);
+ TREE_TYPE (decl) = error_mark_node;
+ return;
+ }
cp_apply_type_quals_to_decl (cp_type_quals (type), decl);
}
@@ -3,4 +3,4 @@
constexpr auto x; // { dg-error "declaration\[^\n\r]*has no initializer" }
extern struct S s;
-constexpr auto y = s; // { dg-error "has incomplete type" }
+constexpr auto y = s; // { dg-error "incomplete" }
new file mode 100644
@@ -0,0 +1,7 @@
+// { dg-do compile { target c++11 } }
+
+#include <initializer_list>
+
+const auto x = { 1, 2 };
+
+// { dg-final { scan-assembler-not {\.data} } }
@@ -31,7 +31,7 @@ F<T>::bar (const G &)
{
auto s = I;
typedef decltype (s) L;
- auto u =[&](L) { auto t = foo (J::K (), 0); }; // { dg-error "25:declared void" }
+ auto u =[&](L) { auto t = foo (J::K (), 0); }; // { dg-error "25:incomplete|void" }
}
struct B {
typedef int G;
@@ -4,7 +4,7 @@
template <typename T>
auto f (T)
{
- auto a = [](auto ... i) // { dg-prune-output "incomplete type" }
+ auto a = [](auto ... i) // { dg-prune-output "incomplete" }
{
int x[][i] = { 0 }; // { dg-error "not expanded" }
}();
@@ -3,9 +3,9 @@
// { dg-options "" }
extern int a[];
-auto [b] { a }; // { dg-error "has incomplete type" }
+auto [b] { a }; // { dg-error "incomplete" }
// { dg-warning "only available with" "" { target c++14_down } .-1 }
-auto [c] = a; // { dg-error "has incomplete type" }
+auto [c] = a; // { dg-error "incomplete" }
// { dg-warning "only available with" "" { target c++14_down } .-1 }
extern int d[0];
auto [e] { d }; // { dg-error "too many initializers for" }
new file mode 100644
@@ -0,0 +1,64 @@
+// Tangentially to PR c++/80351
+// { dg-do compile { target c++17 } }
+// { dg-options "-Wunused-variable" }
+#include <initializer_list>
+
+// Warnings:
+static int int_s1 = 0; // { dg-warning "defined but not used" }
+static int int_s2 = 0; // { dg-warning "defined but not used" }
+inline static int int_is1 = 0; // { dg-warning "defined but not used" }
+inline static int int_is2 = 0; // { dg-warning "defined but not used" }
+// No warnings:
+constexpr static int int_cs1 = 0; // { dg-bogus "defined but not used" }
+constexpr static int int_cs2 = 0; // { dg-bogus "defined but not used" }
+int int_1 = 0; // { dg-bogus "defined but not used" }
+int int_2 = 0; // { dg-bogus "defined but not used" }
+inline int int_i1 = 0; // { dg-bogus "defined but not used" }
+inline int int_i2 = 0; // { dg-bogus "defined but not used" }
+constexpr int int_c1 = 0; // { dg-bogus "defined but not used" }
+constexpr int int_c2 = 0; // { dg-bogus "defined but not used" }
+
+// Warnings:
+static auto int_as1 = 0; // { dg-warning "defined but not used" }
+static auto int_as2 = 0; // { dg-warning "defined but not used" }
+inline static auto int_ais1 = 0; // { dg-warning "defined but not used" }
+inline static auto int_ais2 = 0; // { dg-warning "defined but not used" }
+// No warnings:
+constexpr static auto int_acs1 = 0; // { dg-bogus "defined but not used" }
+constexpr static auto int_acs2 = 0; // { dg-bogus "defined but not used" }
+auto int_a1 = 0; // { dg-bogus "defined but not used" }
+auto int_a2 = 0; // { dg-bogus "defined but not used" }
+inline auto int_ai1 = 0; // { dg-bogus "defined but not used" }
+inline auto int_ai2 = 0; // { dg-bogus "defined but not used" }
+constexpr auto int_ac1 = 0; // { dg-bogus "defined but not used" }
+constexpr auto int_ac2 = 0; // { dg-bogus "defined but not used" }
+
+// Warnings:
+static std::initializer_list<int> il_s1 = {0, 1}; // { dg-warning "defined but not used" }
+static std::initializer_list<int> il_s2 = {0, 1}; // { dg-warning "defined but not used" }
+inline static std::initializer_list<int> il_is1 = {0, 1}; // { dg-warning "defined but not used" }
+inline static std::initializer_list<int> il_is2 = {0, 1}; // { dg-warning "defined but not used" }
+// No warnings:
+constexpr static std::initializer_list<int> il_cs1 = {0, 1}; // { dg-bogus "defined but not used" }
+constexpr static std::initializer_list<int> il_cs2 = {0, 1}; // { dg-bogus "defined but not used" }
+std::initializer_list<int> il_1 = {0, 1}; // { dg-bogus "defined but not used" }
+std::initializer_list<int> il_2 = {0, 1}; // { dg-bogus "defined but not used" }
+inline std::initializer_list<int> il_i1 = {0, 1}; // { dg-bogus "defined but not used" }
+inline std::initializer_list<int> il_i2 = {0, 1}; // { dg-bogus "defined but not used" }
+constexpr std::initializer_list<int> il_c1 = {0, 1}; // { dg-bogus "defined but not used" }
+constexpr std::initializer_list<int> il_c2 = {0, 1}; // { dg-bogus "defined but not used" }
+
+// Warnings:
+static auto il_as1 = {0, 1}; // { dg-warning "defined but not used" }
+static auto il_as2 = {0, 1}; // { dg-warning "defined but not used" }
+inline static auto il_ais1 = {0, 1}; // { dg-warning "defined but not used" }
+inline static auto il_ais2 = {0, 1}; // { dg-warning "defined but not used" }
+// No warnings:
+constexpr static auto il_acs1 = {0, 1}; // { dg-bogus "defined but not used" }
+constexpr static auto il_acs2 = {0, 1}; // { dg-bogus "defined but not used" }
+auto il_a1 = {0, 1}; // { dg-bogus "defined but not used" }
+auto il_a2 = {0, 1}; // { dg-bogus "defined but not used" }
+inline auto il_ai1 = {0, 1}; // { dg-bogus "defined but not used" }
+inline auto il_ai2 = {0, 1}; // { dg-bogus "defined but not used" }
+constexpr auto il_ac1 = {0, 1}; // { dg-bogus "defined but not used" }
+constexpr auto il_ac2 = {0, 1}; // { dg-bogus "defined but not used" }
new file mode 100644
@@ -0,0 +1,16 @@
+// PR c++/80351
+// { dg-do compile { target c++11 } }
+// { dg-options "-Wunused-variable" }
+#include <initializer_list>
+
+constexpr auto int_1 = 1; // { dg-bogus "defined but not used" }
+constexpr auto int_2 = 2; // { dg-bogus "defined but not used" }
+
+constexpr auto il_int_1 = {3, 3}; // { dg-bogus "defined but not used" "Triggered by PR80351" }
+constexpr auto il_int_2 = {4, 4}; // { dg-bogus "defined but not used" "Not triggered by PR80351" }
+
+constexpr auto il_uint_1 = {5u, 5u}; // { dg-bogus "defined but not used" "Triggered by PR80351" }
+constexpr auto il_uint_2 = {6u, 6u}; // { dg-bogus "defined but not used" "Not triggered by PR80351" }
+
+constexpr auto uint_1 = 7u; // { dg-bogus "defined but not used" }
+constexpr auto uint_2 = 8u; // { dg-bogus "defined but not used" }
new file mode 100644
@@ -0,0 +1,16 @@
+// PR c++/80351
+// { dg-do compile { target c++11 } }
+// { dg-options "-Wunused-variable" }
+#include <initializer_list>
+
+const auto int_1 = 1; // { dg-bogus "defined but not used" }
+const auto int_2 = 2; // { dg-bogus "defined but not used" }
+
+const auto il_int_1 = {3, 3}; // { dg-bogus "defined but not used" "Triggered by PR80351" }
+const auto il_int_2 = {4, 4}; // { dg-bogus "defined but not used" "Not triggered by PR80351" }
+
+const auto il_uint_1 = {5u, 5u}; // { dg-bogus "defined but not used" "Triggered by PR80351" }
+const auto il_uint_2 = {6u, 6u}; // { dg-bogus "defined but not used" "Not triggered by PR80351" }
+
+const auto uint_1 = 7u; // { dg-bogus "defined but not used" }
+const auto uint_2 = 8u; // { dg-bogus "defined but not used" }