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Diffstat (limited to 'source/d/gcc/patches/PR100102.5357ab75dedef403b0eebf9277d61d1cbeb5898f.patch')
| -rw-r--r-- | source/d/gcc/patches/PR100102.5357ab75dedef403b0eebf9277d61d1cbeb5898f.patch | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/source/d/gcc/patches/PR100102.5357ab75dedef403b0eebf9277d61d1cbeb5898f.patch b/source/d/gcc/patches/PR100102.5357ab75dedef403b0eebf9277d61d1cbeb5898f.patch new file mode 100644 index 00000000..57432468 --- /dev/null +++ b/source/d/gcc/patches/PR100102.5357ab75dedef403b0eebf9277d61d1cbeb5898f.patch @@ -0,0 +1,133 @@ +From 5357ab75dedef403b0eebf9277d61d1cbeb5898f Mon Sep 17 00:00:00 2001 +From: Patrick Palka <ppalka@redhat.com> +Date: Fri, 4 Jun 2021 13:46:53 -0400 +Subject: [PATCH 1/1] c++: tsubst_function_decl and excess arg levels + [PR100102] + +Here, when instantiating the dependent alias template +duration::__is_harmonic with args={{T,U},{int}}, we find ourselves +substituting the function decl _S_gcd. Since we have more arg levels +than _S_gcd has parm levels, an old special case in tsubst_function_decl +causes us to unwantedly reduce args to its innermost level, yielding +args={int}, which leads to a nonsensical substitution into the decl +context and eventually a crash. + +The comment for this special case refers to three examples for which we +ought to see more arg levels than parm levels here, but none of the +examples actually demonstrate this. In the first example, when +defining S<int>::f(U) parms_depth is 2 and args_depth is 1, and +later when instantiating say S<int>::f<char> both depths are 2. In the +second example, when substituting the template friend declaration +parms_depth is 2 and args_depth is 1, and later when instantiating f +both depths are 1. Finally, the third example is invalid since we can't +specialize a member template of an unspecialized class template like +that. + +Given that this reduction code seems no longer relevant for its +documented purpose and that it causes problems as in the PR, this patch +just removes it. Note that as far as bootstrap/regtest is concerned, +this code is dead; the below two tests would be the first to reach it. + + PR c++/100102 + +gcc/cp/ChangeLog: + + * pt.c (tsubst_function_decl): Remove old code for reducing + args when it has excess levels. + +gcc/testsuite/ChangeLog: + + * g++.dg/cpp0x/alias-decl-72.C: New test. + * g++.dg/cpp0x/alias-decl-72a.C: New test. +--- + gcc/cp/pt.c | 39 --------------------- + gcc/testsuite/g++.dg/cpp0x/alias-decl-72.C | 9 +++++ + gcc/testsuite/g++.dg/cpp0x/alias-decl-72a.C | 9 +++++ + 3 files changed, 18 insertions(+), 39 deletions(-) + create mode 100644 gcc/testsuite/g++.dg/cpp0x/alias-decl-72.C + create mode 100644 gcc/testsuite/g++.dg/cpp0x/alias-decl-72a.C + +diff --git a/gcc/cp/pt.c b/gcc/cp/pt.c +index 7211bdc5bbc..744461ed8cb 100644 +--- a/gcc/cp/pt.c ++++ b/gcc/cp/pt.c +@@ -13905,45 +13905,6 @@ tsubst_function_decl (tree t, tree args, tsubst_flags_t complain, + if (tree spec = retrieve_specialization (gen_tmpl, argvec, hash)) + return spec; + } +- +- /* We can see more levels of arguments than parameters if +- there was a specialization of a member template, like +- this: +- +- template <class T> struct S { template <class U> void f(); } +- template <> template <class U> void S<int>::f(U); +- +- Here, we'll be substituting into the specialization, +- because that's where we can find the code we actually +- want to generate, but we'll have enough arguments for +- the most general template. +- +- We also deal with the peculiar case: +- +- template <class T> struct S { +- template <class U> friend void f(); +- }; +- template <class U> void f() {} +- template S<int>; +- template void f<double>(); +- +- Here, the ARGS for the instantiation of will be {int, +- double}. But, we only need as many ARGS as there are +- levels of template parameters in CODE_PATTERN. We are +- careful not to get fooled into reducing the ARGS in +- situations like: +- +- template <class T> struct S { template <class U> void f(U); } +- template <class T> template <> void S<T>::f(int) {} +- +- which we can spot because the pattern will be a +- specialization in this case. */ +- int args_depth = TMPL_ARGS_DEPTH (args); +- int parms_depth = +- TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t))); +- +- if (args_depth > parms_depth && !DECL_TEMPLATE_SPECIALIZATION (t)) +- args = get_innermost_template_args (args, parms_depth); + } + else + { +diff --git a/gcc/testsuite/g++.dg/cpp0x/alias-decl-72.C b/gcc/testsuite/g++.dg/cpp0x/alias-decl-72.C +new file mode 100644 +index 00000000000..8009756dcba +--- /dev/null ++++ b/gcc/testsuite/g++.dg/cpp0x/alias-decl-72.C +@@ -0,0 +1,9 @@ ++// PR c++/100102 ++// { dg-do compile { target c++11 } } ++ ++template<int()> struct ratio; ++template<class T, class U> struct duration { ++ static constexpr int _S_gcd(); ++ template<class> using __is_harmonic = ratio<_S_gcd>; ++ using type = __is_harmonic<int>; ++}; +diff --git a/gcc/testsuite/g++.dg/cpp0x/alias-decl-72a.C b/gcc/testsuite/g++.dg/cpp0x/alias-decl-72a.C +new file mode 100644 +index 00000000000..a4443e18f9d +--- /dev/null ++++ b/gcc/testsuite/g++.dg/cpp0x/alias-decl-72a.C +@@ -0,0 +1,9 @@ ++// PR c++/100102 ++// { dg-do compile { target c++11 } } ++ ++template<int> struct ratio; ++template<class T> struct duration { ++ static constexpr int _S_gcd(); ++ template<class> using __is_harmonic = ratio<(duration::_S_gcd)()>; ++ using type = __is_harmonic<int>; ++}; +-- +2.27.0 + + |