diff options
| -rw-r--r-- | gcc/c-family/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/c-family/c-common.c | 7 | ||||
| -rw-r--r-- | gcc/testsuite/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/testsuite/g++.dg/warn/Wunused-var-26.C | 147 |
4 files changed, 164 insertions, 1 deletions
diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog index 0a7fef1d3ee..4afb4b8af6e 100644 --- a/gcc/c-family/ChangeLog +++ b/gcc/c-family/ChangeLog @@ -1,3 +1,9 @@ +2017-03-21 Martin Sebor <msebor@redhat.com> + + PR c++/79548 + * c-common.c (set_underlying_type): Mark type used only when + original del is declared unused. + 2017-03-10 David Malcolm <dmalcolm@redhat.com> PR translation/79848 diff --git a/gcc/c-family/c-common.c b/gcc/c-family/c-common.c index 885ea6d2d70..65ffd8cd7bd 100644 --- a/gcc/c-family/c-common.c +++ b/gcc/c-family/c-common.c @@ -7476,7 +7476,12 @@ set_underlying_type (tree x) tt = build_variant_type_copy (tt); TYPE_STUB_DECL (tt) = TYPE_STUB_DECL (DECL_ORIGINAL_TYPE (x)); TYPE_NAME (tt) = x; - TREE_USED (tt) = TREE_USED (x); + + /* Mark the type as used only when its type decl is decorated + with attribute unused. */ + if (lookup_attribute ("unused", DECL_ATTRIBUTES (x))) + TREE_USED (tt) = 1; + TREE_TYPE (x) = tt; } } diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index aa6ec43ebc0..4dbc7197779 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2017-03-21 Martin Sebor <msebor@redhat.com> + + PR c++/79548 + * g++.dg/warn/Wunused-var-26.C: New test. + 2017-03-21 Bill Schmidt <wschmidt@linux.vnet.ibm.com> PR tree-optimization/79908 diff --git a/gcc/testsuite/g++.dg/warn/Wunused-var-26.C b/gcc/testsuite/g++.dg/warn/Wunused-var-26.C new file mode 100644 index 00000000000..b3e020b6007 --- /dev/null +++ b/gcc/testsuite/g++.dg/warn/Wunused-var-26.C @@ -0,0 +1,147 @@ +// PR c++/79548 - missing -Wunused-variable on a typedef'd variable +// in a function template +// { dg-do compile } +// { dg-options "-Wunused" } + + +#define UNUSED __attribute__ ((unused)) + +template <class T> +void f_int () +{ + T t; // { dg-warning "unused variable" } + + typedef T U; + U u; // { dg-warning "unused variable" } +} + +template void f_int<int>(); + + +template <class T> +void f_intptr () +{ + T *t = 0; // { dg-warning "unused variable" } + + typedef T U; + U *u = 0; // { dg-warning "unused variable" } +} + +template void f_intptr<int>(); + + +template <class T> +void f_var_unused () +{ + // The variable is marked unused. + T t UNUSED; + + typedef T U; + U u UNUSED; +} + +template void f_var_unused<int>(); + + +template <class T> +void f_var_type_unused () +{ + // The variable's type is marked unused. + T* UNUSED t = new T; // { dg-bogus "unused variable" "bug 79585" { xfail *-*-* } } + + typedef T U; + U* UNUSED u = new U; // { dg-bogus "unused variable" "bug 79585" { xfail *-*-* } } + + typedef T UNUSED U; + U v = U (); // { dg-bogus "unused variable" "bug 79585" } +} + +template void f_var_type_unused<int>(); + + +struct A { int i; }; + +template <class T> +void f_A () +{ + T t; // { dg-warning "unused variable" } + + typedef T U; + U u; // { dg-warning "unused variable" } +} + +template void f_A<A>(); + + +template <class T> +void f_A_unused () +{ + T t UNUSED; + + typedef T U; + U u UNUSED; +} + +template void f_A_unused<A>(); + + +struct B { B (); }; + +template <class T> +void f_B () +{ + T t; + + typedef T U; + U u; +} + +template void f_B<B>(); + + +struct NonTrivialDtor { ~NonTrivialDtor (); }; + +template <class T> +void f_with_NonTrivialDtor () +{ + // Expect no warnings when instantiated on a type with a non-trivial + // destructor. + T t; + + typedef T U; + U u; +} + +template void f_with_NonTrivialDtor<NonTrivialDtor>(); + + +struct D { NonTrivialDtor b; }; + +template <class T> +void f_D () +{ + // Same as f_with_NonTrivialDtor but with a class that has a member + // with a non-trivial dtor. + T t; + + typedef T U; + U u; +} + +template void f_D<D>(); + + +struct UNUSED DeclaredUnused { }; + +template <class T> +void f_with_unused () +{ + // Expect no warnings when instantiatiated on a type declared + // with attribute unused. + T t; + + typedef T U; + U u; +} + +template void f_with_unused<DeclaredUnused>(); |