On 11/6/20 1:15 AM, Marek Polacek wrote:
While messing with check_handlers_1, I spotted this bug report which
complains that we don't warn about the case when we have two duplicated
handlers of type int. can_convert_eh implements [except.handle] and
that says: A handler is a match for an exception object of type E if
- The handler is of type cv T or cv T& and E and T are the same type
(ignoring the top-level cv-qualifiers), or [...]
but we don't implement this bullet properly for non-class types. The
fix therefore seems pretty obvious. Also change the return type to
bool when we're only returning yes/no.
OK.
gcc/cp/ChangeLog:
PR c++/81660
* except.c (can_convert_eh): Change the return type to bool. If
the type TO and FROM are the same, return true.
gcc/testsuite/ChangeLog:
PR c++/81660
* g++.dg/warn/Wexceptions3.C: New test.
* g++.dg/eh/pr42859.C: Add dg-warning.
* g++.dg/torture/pr81659.C: Likewise.
---
gcc/cp/except.c | 14 +++++++-----
gcc/testsuite/g++.dg/eh/pr42859.C | 2 +-
gcc/testsuite/g++.dg/torture/pr81659.C | 2 +-
gcc/testsuite/g++.dg/warn/Wexceptions3.C | 29 ++++++++++++++++++++++++
4 files changed, 39 insertions(+), 8 deletions(-)
create mode 100644 gcc/testsuite/g++.dg/warn/Wexceptions3.C
diff --git a/gcc/cp/except.c b/gcc/cp/except.c
index b72a28c1aa9..0f6c76b9892 100644
--- a/gcc/cp/except.c
+++ b/gcc/cp/except.c
@@ -41,7 +41,6 @@ static tree do_allocate_exception (tree);
static tree wrap_cleanups_r (tree *, int *, void *);
static int complete_ptr_ref_or_void_ptr_p (tree, tree);
static bool is_admissible_throw_operand_or_catch_parameter (tree, bool);
-static int can_convert_eh (tree, tree);
/* Sets up all the global eh stuff that needs to be initialized at the
start of compilation. */
@@ -932,31 +931,34 @@ nothrow_libfn_p (const_tree fn)
/* Returns nonzero if an exception of type FROM will be caught by a
handler for type TO, as per [except.handle]. */
-static int
+static bool
can_convert_eh (tree to, tree from)
{
to = non_reference (to);
from = non_reference (from);
+ if (same_type_ignoring_top_level_qualifiers_p (to, from))
+ return true;
+
if (TYPE_PTR_P (to) && TYPE_PTR_P (from))
{
to = TREE_TYPE (to);
from = TREE_TYPE (from);
if (! at_least_as_qualified_p (to, from))
- return 0;
+ return false;
if (VOID_TYPE_P (to))
- return 1;
+ return true;
/* Else fall through. */
}
if (CLASS_TYPE_P (to) && CLASS_TYPE_P (from)
&& publicly_uniquely_derived_p (to, from))
- return 1;
+ return true;
- return 0;
+ return false;
}
/* Check whether any of the handlers in I are shadowed by another handler
diff --git a/gcc/testsuite/g++.dg/eh/pr42859.C
b/gcc/testsuite/g++.dg/eh/pr42859.C
index a9f1473bc85..0de91409c83 100644
--- a/gcc/testsuite/g++.dg/eh/pr42859.C
+++ b/gcc/testsuite/g++.dg/eh/pr42859.C
@@ -13,7 +13,7 @@ ptw32_terminate (void)
catch (int)
{
}
- catch (int)
+ catch (int) // { dg-warning "will be caught by earlier handler" }
{
}
}
diff --git a/gcc/testsuite/g++.dg/torture/pr81659.C
b/gcc/testsuite/g++.dg/torture/pr81659.C
index 3696957532e..074099be6fc 100644
--- a/gcc/testsuite/g++.dg/torture/pr81659.C
+++ b/gcc/testsuite/g++.dg/torture/pr81659.C
@@ -12,7 +12,7 @@ a (int b)
catch (int)
{
}
- catch (int)
+ catch (int) // { dg-warning "will be caught by earlier handler" }
{
}
}
diff --git a/gcc/testsuite/g++.dg/warn/Wexceptions3.C
b/gcc/testsuite/g++.dg/warn/Wexceptions3.C
new file mode 100644
index 00000000000..97fda9dbd91
--- /dev/null
+++ b/gcc/testsuite/g++.dg/warn/Wexceptions3.C
@@ -0,0 +1,29 @@
+// PR c++/81660
+
+void bar (int);
+
+void
+fn (int b)
+{
+ if (b)
+ throw;
+ try
+ {
+ bar (3);
+ }
+ catch (int)
+ {
+ }
+ catch (int) // { dg-warning "will be caught by earlier handler" }
+ {
+ }
+ catch (const int) // { dg-warning "will be caught by earlier handler" }
+ {
+ }
+ catch (int &) // { dg-warning "will be caught by earlier handler" }
+ {
+ }
+ catch (const int &) // { dg-warning "will be caught by earlier handler" }
+ {
+ }
+}
base-commit: f72af3af8d526793e4927daf44ae0611c3d0cc85
