libiberty: Invoke D demangler when --format=auto
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Commit Message
Investigating GDB PR d/31580 showed that the libiberty demangler
doesn't automatically demangle D mangled names. However, I think it
should -- like C++ and Rust (new-style), D mangled names are readily
distinguished by the leading "_D", and so the likelihood of confusion
is low. The other non-"auto" cases in this code are Ada (where the
encoded form could more easily be confused by ordinary programs) and
Java (which is long gone, but which also shared the C++ mangling and
thus was just an output style preference).
This patch also fixed another GDB bug, though of course that part
won't apply to the GCC repository.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31580
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30276
libiberty
* cplus-dem.c (cplus_demangle): Try the D demangler with
"auto" format.
* testsuite/d-demangle-expected: Add --format=auto test.
---
gdb/testsuite/gdb.dlang/dlang-start-2.exp | 4 +---
libiberty/cplus-dem.c | 2 +-
libiberty/testsuite/d-demangle-expected | 5 +++++
3 files changed, 7 insertions(+), 4 deletions(-)
Comments
On Sat, Mar 30, 2024 at 9:11 PM Tom Tromey <tom@tromey.com> wrote:
>
> Investigating GDB PR d/31580 showed that the libiberty demangler
> doesn't automatically demangle D mangled names. However, I think it
> should -- like C++ and Rust (new-style), D mangled names are readily
> distinguished by the leading "_D", and so the likelihood of confusion
> is low. The other non-"auto" cases in this code are Ada (where the
> encoded form could more easily be confused by ordinary programs) and
> Java (which is long gone, but which also shared the C++ mangling and
> thus was just an output style preference).
>
> This patch also fixed another GDB bug, though of course that part
> won't apply to the GCC repository.
OK.
> Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31580
> Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30276
>
> libiberty
> * cplus-dem.c (cplus_demangle): Try the D demangler with
> "auto" format.
> * testsuite/d-demangle-expected: Add --format=auto test.
> ---
> gdb/testsuite/gdb.dlang/dlang-start-2.exp | 4 +---
> libiberty/cplus-dem.c | 2 +-
> libiberty/testsuite/d-demangle-expected | 5 +++++
> 3 files changed, 7 insertions(+), 4 deletions(-)
>
> diff --git a/gdb/testsuite/gdb.dlang/dlang-start-2.exp b/gdb/testsuite/gdb.dlang/dlang-start-2.exp
> index 4b3163ec97d..284f841b54a 100644
> --- a/gdb/testsuite/gdb.dlang/dlang-start-2.exp
> +++ b/gdb/testsuite/gdb.dlang/dlang-start-2.exp
> @@ -79,10 +79,8 @@ if {[gdb_start_cmd] < 0} {
> return -1
> }
>
> -# We should probably have "D main" instead of "_Dmain" here, filed PR30276
> -# '[gdb/symtab] function name is _Dmain instead of "D main"' about that.
> gdb_test "" \
> - "in _Dmain \\(\\)" \
> + "in D main \\(\\)" \
> "start"
>
> gdb_test "show language" {"auto; currently d".}
> diff --git a/libiberty/cplus-dem.c b/libiberty/cplus-dem.c
> index 8b92946981f..ee9e84f5d6b 100644
> --- a/libiberty/cplus-dem.c
> +++ b/libiberty/cplus-dem.c
> @@ -186,7 +186,7 @@ cplus_demangle (const char *mangled, int options)
> if (GNAT_DEMANGLING)
> return ada_demangle (mangled, options);
>
> - if (DLANG_DEMANGLING)
> + if (DLANG_DEMANGLING || AUTO_DEMANGLING)
> {
> ret = dlang_demangle (mangled, options);
> if (ret)
> diff --git a/libiberty/testsuite/d-demangle-expected b/libiberty/testsuite/d-demangle-expected
> index 47b059c4298..cfbdf2a52cb 100644
> --- a/libiberty/testsuite/d-demangle-expected
> +++ b/libiberty/testsuite/d-demangle-expected
> @@ -1470,3 +1470,8 @@ demangle.anonymous
> --format=dlang
> _D8demangle9anonymous03fooZ
> demangle.anonymous.foo
> +#
> +# Test that 'auto' works.
> +--format=auto
> +_D8demangle9anonymous03fooZ
> +demangle.anonymous.foo
> --
> 2.43.0
>
@@ -79,10 +79,8 @@ if {[gdb_start_cmd] < 0} {
return -1
}
-# We should probably have "D main" instead of "_Dmain" here, filed PR30276
-# '[gdb/symtab] function name is _Dmain instead of "D main"' about that.
gdb_test "" \
- "in _Dmain \\(\\)" \
+ "in D main \\(\\)" \
"start"
gdb_test "show language" {"auto; currently d".}
@@ -186,7 +186,7 @@ cplus_demangle (const char *mangled, int options)
if (GNAT_DEMANGLING)
return ada_demangle (mangled, options);
- if (DLANG_DEMANGLING)
+ if (DLANG_DEMANGLING || AUTO_DEMANGLING)
{
ret = dlang_demangle (mangled, options);
if (ret)
@@ -1470,3 +1470,8 @@ demangle.anonymous
--format=dlang
_D8demangle9anonymous03fooZ
demangle.anonymous.foo
+#
+# Test that 'auto' works.
+--format=auto
+_D8demangle9anonymous03fooZ
+demangle.anonymous.foo