Re: [PATCH] c++: unifying REAL_CSTs [PR110809]

[Jason Merrill via Gcc-patches]

On 7/26/23 12:57, Patrick Palka wrote:

Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
trunk/13 (after the branch is unfrozen)?


OK.


-- >8 --

This teaches unify how to compare two REAL_CSTs.

PR c++/110809

gcc/cp/ChangeLog:

* pt.cc (unify) : Generalize to handle
REAL_CST as well.

gcc/testsuite/ChangeLog:

* g++.dg/cpp2a/nontype-float3.C: New test.
---
  gcc/cp/pt.cc|  5 +++--
  gcc/testsuite/g++.dg/cpp2a/nontype-float3.C | 12 
  2 files changed, 15 insertions(+), 2 deletions(-)
  create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-float3.C

diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index d342ab5929a..1e09f304490 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -24890,12 +24890,13 @@ unify (tree tparms, tree targs, tree parm, tree arg, 
int strict,
/* Types INTEGER_CST and MINUS_EXPR can come from array bounds.  */
/* Type INTEGER_CST can come from ordinary constant template args.  */
  case INTEGER_CST:
+case REAL_CST:
while (CONVERT_EXPR_P (arg))
arg = TREE_OPERAND (arg, 0);
  
-  if (TREE_CODE (arg) != INTEGER_CST)

+  if (TREE_CODE (arg) != TREE_CODE (parm))
return unify_template_argument_mismatch (explain_p, parm, arg);
-  return (tree_int_cst_equal (parm, arg)
+  return (simple_cst_equal (parm, arg)
  ? unify_success (explain_p)
  : unify_template_argument_mismatch (explain_p, parm, arg));
  
diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-float3.C b/gcc/testsuite/g++.dg/cpp2a/nontype-float3.C

new file mode 100644
index 000..044fb99905a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/nontype-float3.C
@@ -0,0 +1,12 @@
+// PR c++/110809
+// { dg-do compile { target c++20 } }
+
+template struct A { };
+
+template void f(A);
+template void f(A);
+
+int main() {
+  f(A{});
+  f(A{}); // { dg-error "no match" }
+}

[PATCH] c++: unifying REAL_CSTs [PR110809]

[Patrick Palka via Gcc-patches]

Bootstrapped and regtested on x86_64-pc-linux-gnu, does this look OK for
trunk/13 (after the branch is unfrozen)?

-- >8 --

This teaches unify how to compare two REAL_CSTs.

PR c++/110809

gcc/cp/ChangeLog:

* pt.cc (unify) : Generalize to handle
REAL_CST as well.

gcc/testsuite/ChangeLog:

* g++.dg/cpp2a/nontype-float3.C: New test.
---
 gcc/cp/pt.cc|  5 +++--
 gcc/testsuite/g++.dg/cpp2a/nontype-float3.C | 12 
 2 files changed, 15 insertions(+), 2 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/cpp2a/nontype-float3.C

diff --git a/gcc/cp/pt.cc b/gcc/cp/pt.cc
index d342ab5929a..1e09f304490 100644
--- a/gcc/cp/pt.cc
+++ b/gcc/cp/pt.cc
@@ -24890,12 +24890,13 @@ unify (tree tparms, tree targs, tree parm, tree arg, 
int strict,
   /* Types INTEGER_CST and MINUS_EXPR can come from array bounds.  */
   /* Type INTEGER_CST can come from ordinary constant template args.  */
 case INTEGER_CST:
+case REAL_CST:
   while (CONVERT_EXPR_P (arg))
arg = TREE_OPERAND (arg, 0);
 
-  if (TREE_CODE (arg) != INTEGER_CST)
+  if (TREE_CODE (arg) != TREE_CODE (parm))
return unify_template_argument_mismatch (explain_p, parm, arg);
-  return (tree_int_cst_equal (parm, arg)
+  return (simple_cst_equal (parm, arg)
  ? unify_success (explain_p)
  : unify_template_argument_mismatch (explain_p, parm, arg));
 
diff --git a/gcc/testsuite/g++.dg/cpp2a/nontype-float3.C 
b/gcc/testsuite/g++.dg/cpp2a/nontype-float3.C
new file mode 100644
index 000..044fb99905a
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp2a/nontype-float3.C
@@ -0,0 +1,12 @@
+// PR c++/110809
+// { dg-do compile { target c++20 } }
+
+template struct A { };
+
+template void f(A);
+template void f(A);
+
+int main() {
+  f(A{});
+  f(A{}); // { dg-error "no match" }
+}
-- 
2.41.0.450.ga80be15292