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author | Patrick Palka <ppalka@redhat.com> | 2021-05-26 08:35:31 -0400 |
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committer | Patrick Palka <ppalka@redhat.com> | 2023-06-30 00:03:14 -0400 |
commit | ad42219766d0e67bede2c9bd94c98082cde42518 (patch) | |
tree | b08ab0f677cb6fded649214f46ca8b80432fae9e /gcc | |
parent | c48f10004ebc60976294488c59c9df828120db32 (diff) | |
download | gcc-ad42219766d0e67bede2c9bd94c98082cde42518.zip gcc-ad42219766d0e67bede2c9bd94c98082cde42518.tar.gz gcc-ad42219766d0e67bede2c9bd94c98082cde42518.tar.bz2 |
c++: Fix reference NTTP binding to noexcept fn [PR97420]
Here, in C++17 mode, convert_nontype_argument_function is rejecting
binding a non-noexcept function reference template parameter to a
noexcept function (encoded as the template argument '*(int (&) (int)) &f').
The first roadblock to making this work is that the argument is wrapped
an an implicit INDIRECT_REF, so we need to unwrap it before calling
strip_fnptr_conv.
The second roadblock is that the NOP_EXPR cast converts from a function
pointer type to a reference type while simultaneously removing the
noexcept qualification, and fnptr_conv_p doesn't consider this cast to
be a function pointer conversion. This patch fixes this by making
fnptr_conv_p treat REFERENCE_TYPEs and POINTER_TYPEs interchangeably.
Finally, in passing, this patch also simplifies noexcept_conv_p by
removing a bunch of redundant checks already performed by its only
caller fnptr_conv_p.
PR c++/97420
gcc/cp/ChangeLog:
* cvt.c (noexcept_conv_p): Remove redundant checks and simplify.
(fnptr_conv_p): Don't call non_reference. Use INDIRECT_TYPE_P
instead of TYPE_PTR_P.
* pt.c (convert_nontype_argument_function): Look through
implicit INDIRECT_REFs before calling strip_fnptr_conv.
gcc/testsuite/ChangeLog:
* g++.dg/cpp0x/noexcept68.C: New test.
(cherry picked from commit b4329e3dd6fb7c78948fcf9d2f5b9d873deec284)
Diffstat (limited to 'gcc')
-rw-r--r-- | gcc/cp/cvt.c | 36 | ||||
-rw-r--r-- | gcc/cp/pt.c | 5 | ||||
-rw-r--r-- | gcc/testsuite/g++.dg/cpp0x/noexcept68.C | 8 |
3 files changed, 23 insertions, 26 deletions
diff --git a/gcc/cp/cvt.c b/gcc/cp/cvt.c index 0e11f06..fe3282f 100644 --- a/gcc/cp/cvt.c +++ b/gcc/cp/cvt.c @@ -2072,7 +2072,8 @@ can_convert_tx_safety (tree to, tree from) && same_type_p (to, tx_unsafe_fn_variant (from))); } -/* Return true iff FROM can convert to TO by dropping noexcept. */ +/* Return true iff FROM can convert to TO by dropping noexcept. + This is just a subroutine of of fnptr_conv_p. */ static bool noexcept_conv_p (tree to, tree from) @@ -2080,30 +2081,15 @@ noexcept_conv_p (tree to, tree from) if (!flag_noexcept_type) return false; - tree t = non_reference (to); - tree f = from; - if (TYPE_PTRMEMFUNC_P (t) - && TYPE_PTRMEMFUNC_P (f)) - { - t = TYPE_PTRMEMFUNC_FN_TYPE (t); - f = TYPE_PTRMEMFUNC_FN_TYPE (f); - } - if (TYPE_PTR_P (t) - && TYPE_PTR_P (f)) - { - t = TREE_TYPE (t); - f = TREE_TYPE (f); - } - tree_code code = TREE_CODE (f); - if (TREE_CODE (t) != code) + if (TREE_CODE (to) != TREE_CODE (from)) return false; - if (code != FUNCTION_TYPE && code != METHOD_TYPE) + if (!FUNC_OR_METHOD_TYPE_P (from)) return false; - if (!type_throw_all_p (t) - || type_throw_all_p (f)) + if (!type_throw_all_p (to) + || type_throw_all_p (from)) return false; - tree v = build_exception_variant (f, NULL_TREE); - return same_type_p (t, v); + tree v = build_exception_variant (from, NULL_TREE); + return same_type_p (to, v); } /* Return true iff FROM can convert to TO by a function pointer conversion. */ @@ -2111,7 +2097,7 @@ noexcept_conv_p (tree to, tree from) bool fnptr_conv_p (tree to, tree from) { - tree t = non_reference (to); + tree t = to; tree f = from; if (TYPE_PTRMEMFUNC_P (t) && TYPE_PTRMEMFUNC_P (f)) @@ -2119,8 +2105,8 @@ fnptr_conv_p (tree to, tree from) t = TYPE_PTRMEMFUNC_FN_TYPE (t); f = TYPE_PTRMEMFUNC_FN_TYPE (f); } - if (TYPE_PTR_P (t) - && TYPE_PTR_P (f)) + if (INDIRECT_TYPE_P (t) + && INDIRECT_TYPE_P (f)) { t = TREE_TYPE (t); f = TREE_TYPE (f); diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c index 1185cdc..448da25 100644 --- a/gcc/cp/pt.c +++ b/gcc/cp/pt.c @@ -6559,7 +6559,10 @@ convert_nontype_argument_function (tree type, tree expr, if (value_dependent_expression_p (fn)) goto accept; - fn_no_ptr = strip_fnptr_conv (fn); + fn_no_ptr = fn; + if (REFERENCE_REF_P (fn_no_ptr)) + fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0); + fn_no_ptr = strip_fnptr_conv (fn_no_ptr); if (TREE_CODE (fn_no_ptr) == ADDR_EXPR) fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0); if (BASELINK_P (fn_no_ptr)) diff --git a/gcc/testsuite/g++.dg/cpp0x/noexcept68.C b/gcc/testsuite/g++.dg/cpp0x/noexcept68.C new file mode 100644 index 0000000..086899a --- /dev/null +++ b/gcc/testsuite/g++.dg/cpp0x/noexcept68.C @@ -0,0 +1,8 @@ +// PR c++/97420 +// { dg-do compile { target c++11 } } + +int f(int) noexcept; +template<int (&)(int)> void A(); +int main() { + A<f>(); +} |