| Message ID | 20190829173614.GN14737@redhat.com |
|---|---|
| State | New |
| Headers | show |
| Series | C++ PATCH for c++/91129 - wrong error with binary op in template argument | expand |
On 8/29/19 12:36 PM, Marek Polacek wrote: > We reject this test with errors like > > nontype1.C:22:14: error: taking address of rvalue [-fpermissive] > 22 | A<int, N / C<int, 6>{}> a2; > | ^~~~~~~~~~~ > > that happens because for converting "C<int, 6>{}" to int we generate > "C<int, 6>::operator int (&TARGET_EXPR <D.1234, {}>)". The second > template argument is a binary operator, so while parsing the template > arguments in a function template foo we end up in cp_build_binary_op. > > cp_build_binary_op calls, for certain binary ops, fold_non_dependent_expr. > Since <https://gcc.gnu.org/ml/gcc-patches/2018-06/msg01475.html> these > calls are no longer tf_none. fold_non_dependent_expr, when in a template, > will instantiate, which gives the "taking address of rvalue" error. > > In this particular case the fix seems to be using fold_for_warn instead, > which in a template is fold_non_dependent_expr with tf_none; all the > fold calls I'm changing in this patch are used for diagnostic purposes > only, and it fixes all the bogus errors. > > Bootstrapped/regtested on x86_64-linux, ok for trunk? > > 2019-08-29 Marek Polacek <polacek@redhat.com> > > PR c++/91129 - wrong error with binary op in template argument. > * typeck.c (warn_for_null_address): Use fold_for_warn instead of > fold_non_dependent_expr. > (cp_build_binary_op): Likewise. > > * g++.dg/cpp1y/nontype1.C: New test. > > diff --git gcc/cp/typeck.c gcc/cp/typeck.c > index c09bb309142..31414453524 100644 > --- gcc/cp/typeck.c > +++ gcc/cp/typeck.c > @@ -4305,7 +4305,7 @@ warn_for_null_address (location_t location, tree op, tsubst_flags_t complain) > || TREE_NO_WARNING (op)) > return; > > - tree cop = fold_non_dependent_expr (op, complain); > + tree cop = fold_for_warn (op); > > if (TREE_CODE (cop) == ADDR_EXPR > && decl_with_nonnull_addr_p (TREE_OPERAND (cop, 0)) > @@ -4628,9 +4628,8 @@ cp_build_binary_op (const op_location_t &location, > || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)) > { > enum tree_code tcode0 = code0, tcode1 = code1; > - tree cop1 = fold_non_dependent_expr (op1, complain); > doing_div_or_mod = true; > - warn_for_div_by_zero (location, cop1); > + warn_for_div_by_zero (location, fold_for_warn (op1)); > > if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE) > tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0))); > @@ -4669,11 +4668,8 @@ cp_build_binary_op (const op_location_t &location, > > case TRUNC_MOD_EXPR: > case FLOOR_MOD_EXPR: > - { > - tree cop1 = fold_non_dependent_expr (op1, complain); > - doing_div_or_mod = true; > - warn_for_div_by_zero (location, cop1); > - } > + doing_div_or_mod = true; > + warn_for_div_by_zero (location, fold_for_warn (op1)); > > if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE > && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE > @@ -4766,7 +4762,7 @@ cp_build_binary_op (const op_location_t &location, > } > else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) > { > - tree const_op1 = fold_non_dependent_expr (op1, complain); > + tree const_op1 = fold_for_warn (op1); > if (TREE_CODE (const_op1) != INTEGER_CST) > const_op1 = op1; > result_type = type0; > @@ -4812,10 +4808,10 @@ cp_build_binary_op (const op_location_t &location, > } > else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) > { > - tree const_op0 = fold_non_dependent_expr (op0, complain); > + tree const_op0 = fold_for_warn (op0); > if (TREE_CODE (const_op0) != INTEGER_CST) > const_op0 = op0; > - tree const_op1 = fold_non_dependent_expr (op1, complain); > + tree const_op1 = fold_for_warn (op1); > if (TREE_CODE (const_op1) != INTEGER_CST) > const_op1 = op1; > result_type = type0; > diff --git gcc/testsuite/g++.dg/cpp1y/nontype1.C gcc/testsuite/g++.dg/cpp1y/nontype1.C > new file mode 100644 > index 00000000000..a37e996a3ff > --- /dev/null > +++ gcc/testsuite/g++.dg/cpp1y/nontype1.C > @@ -0,0 +1,42 @@ > +// PR c++/91129 - wrong error with binary op in template argument. > +// { dg-do compile { target c++14 } } > + > +template<class T, T v> > +struct C > +{ > + constexpr operator T() const { return v; } > + constexpr auto operator()() const { return v; } > +}; > + > +template<class T, int N> > +struct A > +{ > +}; > + > +template<int N> > +void foo () > +{ > + A<int, C<int, 6>{}> a0; > + A<int, !C<int, 6>{}> a1; > + A<int, N / C<int, 6>{}> a2; > + A<int, N % C<int, 6>{}> a3; > + A<int, N * C<int, 6>{}> a4; > + A<int, N ^ C<int, 6>{}> a5; > + A<int, N | C<int, 6>{}> a6; > + A<int, N & C<int, 6>{}> a7; > + A<int, N + C<int, 6>{}> a8; > + A<int, N - C<int, 6>{}> a9; > + A<int, -C<int, 6>{}> a10; > + A<int, (N >> C<int, 6>{})> a11; > + A<int, N << C<int, 6>{}> a12; > + A<int, ~C<int, 6>{}> a13; > + A<int, N || C<int, 6>{}> a14; > + A<int, N && C<int, 6>{}> a15; > + A<int, N == C<int, 6>{}> a16; > + A<int, N != C<int, 6>{}> a17; > +} > + > +int main() > +{ > + foo<10>(); > +} > OK. Jason
diff --git gcc/cp/typeck.c gcc/cp/typeck.c index c09bb309142..31414453524 100644 --- gcc/cp/typeck.c +++ gcc/cp/typeck.c @@ -4305,7 +4305,7 @@ warn_for_null_address (location_t location, tree op, tsubst_flags_t complain) || TREE_NO_WARNING (op)) return; - tree cop = fold_non_dependent_expr (op, complain); + tree cop = fold_for_warn (op); if (TREE_CODE (cop) == ADDR_EXPR && decl_with_nonnull_addr_p (TREE_OPERAND (cop, 0)) @@ -4628,9 +4628,8 @@ cp_build_binary_op (const op_location_t &location, || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)) { enum tree_code tcode0 = code0, tcode1 = code1; - tree cop1 = fold_non_dependent_expr (op1, complain); doing_div_or_mod = true; - warn_for_div_by_zero (location, cop1); + warn_for_div_by_zero (location, fold_for_warn (op1)); if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE) tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0))); @@ -4669,11 +4668,8 @@ cp_build_binary_op (const op_location_t &location, case TRUNC_MOD_EXPR: case FLOOR_MOD_EXPR: - { - tree cop1 = fold_non_dependent_expr (op1, complain); - doing_div_or_mod = true; - warn_for_div_by_zero (location, cop1); - } + doing_div_or_mod = true; + warn_for_div_by_zero (location, fold_for_warn (op1)); if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE @@ -4766,7 +4762,7 @@ cp_build_binary_op (const op_location_t &location, } else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) { - tree const_op1 = fold_non_dependent_expr (op1, complain); + tree const_op1 = fold_for_warn (op1); if (TREE_CODE (const_op1) != INTEGER_CST) const_op1 = op1; result_type = type0; @@ -4812,10 +4808,10 @@ cp_build_binary_op (const op_location_t &location, } else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE) { - tree const_op0 = fold_non_dependent_expr (op0, complain); + tree const_op0 = fold_for_warn (op0); if (TREE_CODE (const_op0) != INTEGER_CST) const_op0 = op0; - tree const_op1 = fold_non_dependent_expr (op1, complain); + tree const_op1 = fold_for_warn (op1); if (TREE_CODE (const_op1) != INTEGER_CST) const_op1 = op1; result_type = type0; diff --git gcc/testsuite/g++.dg/cpp1y/nontype1.C gcc/testsuite/g++.dg/cpp1y/nontype1.C new file mode 100644 index 00000000000..a37e996a3ff --- /dev/null +++ gcc/testsuite/g++.dg/cpp1y/nontype1.C @@ -0,0 +1,42 @@ +// PR c++/91129 - wrong error with binary op in template argument. +// { dg-do compile { target c++14 } } + +template<class T, T v> +struct C +{ + constexpr operator T() const { return v; } + constexpr auto operator()() const { return v; } +}; + +template<class T, int N> +struct A +{ +}; + +template<int N> +void foo () +{ + A<int, C<int, 6>{}> a0; + A<int, !C<int, 6>{}> a1; + A<int, N / C<int, 6>{}> a2; + A<int, N % C<int, 6>{}> a3; + A<int, N * C<int, 6>{}> a4; + A<int, N ^ C<int, 6>{}> a5; + A<int, N | C<int, 6>{}> a6; + A<int, N & C<int, 6>{}> a7; + A<int, N + C<int, 6>{}> a8; + A<int, N - C<int, 6>{}> a9; + A<int, -C<int, 6>{}> a10; + A<int, (N >> C<int, 6>{})> a11; + A<int, N << C<int, 6>{}> a12; + A<int, ~C<int, 6>{}> a13; + A<int, N || C<int, 6>{}> a14; + A<int, N && C<int, 6>{}> a15; + A<int, N == C<int, 6>{}> a16; + A<int, N != C<int, 6>{}> a17; +} + +int main() +{ + foo<10>(); +}
We reject this test with errors like nontype1.C:22:14: error: taking address of rvalue [-fpermissive] 22 | A<int, N / C<int, 6>{}> a2; | ^~~~~~~~~~~ that happens because for converting "C<int, 6>{}" to int we generate "C<int, 6>::operator int (&TARGET_EXPR <D.1234, {}>)". The second template argument is a binary operator, so while parsing the template arguments in a function template foo we end up in cp_build_binary_op. cp_build_binary_op calls, for certain binary ops, fold_non_dependent_expr. Since <https://gcc.gnu.org/ml/gcc-patches/2018-06/msg01475.html> these calls are no longer tf_none. fold_non_dependent_expr, when in a template, will instantiate, which gives the "taking address of rvalue" error. In this particular case the fix seems to be using fold_for_warn instead, which in a template is fold_non_dependent_expr with tf_none; all the fold calls I'm changing in this patch are used for diagnostic purposes only, and it fixes all the bogus errors. Bootstrapped/regtested on x86_64-linux, ok for trunk? 2019-08-29 Marek Polacek <polacek@redhat.com> PR c++/91129 - wrong error with binary op in template argument. * typeck.c (warn_for_null_address): Use fold_for_warn instead of fold_non_dependent_expr. (cp_build_binary_op): Likewise. * g++.dg/cpp1y/nontype1.C: New test.