[PATCH v3 5/9] gdb/ctf: check return value of ctf_type_align

Simon Marchi
2026-02-28T03:54:59Z

I tried to build the Linux kernel with -gctf. I am not sure if the
result is good, because I got plenty of warnings like:

ld: warning: orphan section `.ctf' from `vmlinux.o' being placed in section `.ctf'

Nevertheless, I tried to load it in GDB, and it didn't complain.
However, when doing "maint expand-symtabs", I did hit this assert:

/home/simark/src/binutils-gdb/gdb/gdbtypes.c:3640: internal-error: set_type_align: Assertion `(align & (align - 1)) == 0' failed.

This is because ctf_type_align returns -1 for some types, which is an
indication of an error. Update the code to check the return value of
ctf_type_align for errors, and emit complaints if it happens.

With this patch, if I enable the complaints, I see a bunch of messages
like this:

During symbol reading: ctf_type_align read_structure_type failed - Type is not a complete type.

Change-Id: Ibed23e7f1490d9163b8dde1318b9e45dec2906d6
---
gdb/ctfread.c | 40 +++++++++++++++++++++++++++++++++++-----
1 file changed, 35 insertions(+), 5 deletions(-)

diff --git a/gdb/ctfread.c b/gdb/ctfread.c
index c8457a70cf46..ed4a7383427d 100644
--- a/gdb/ctfread.c
+++ b/gdb/ctfread.c
@@ -616,7 +616,14 @@ read_structure_type (struct ctf_context *ccp, ctf_id_t tid)
type->set_code (TYPE_CODE_STRUCT);

type->set_length (ctf_type_size (dict, tid));
- set_type_align (type, ctf_type_align (dict, tid));
+
+ if (ssize_t align = ctf_type_align (dict, tid);
+ align >= 0)
+ set_type_align (type, align);
+ else
+ complaint (_("ctf_type_align read_structure_type failed - %s"),
+ ctf_errmsg (ctf_errno (dict)));
+

return set_tid_type (objfile, tid, type);
}
@@ -673,7 +680,13 @@ read_func_kind_type (struct ctf_context *ccp, ctf_id_t tid)
}
rettype = fetch_tid_type (ccp, cfi.ctc_return);
type->set_target_type (rettype);
- set_type_align (type, ctf_type_align (dict, tid));
+
+ if (ssize_t align = ctf_type_align (dict, tid);
+ align >= 0)
+ set_type_align (type, align);
+ else
+ complaint (_("ctf_type_align read_func_kind_type failed - %s"),
+ ctf_errmsg (ctf_errno (dict)));

/* Set up function's arguments. */
argc = cfi.ctc_argc;
@@ -723,7 +736,13 @@ read_enum_type (struct ctf_context *ccp, ctf_id_t tid)
type->set_length (ctf_type_size (dict, tid));
/* Set the underlying type based on its ctf_type_size bits. */
type->set_target_type (objfile_int_type (objfile, type->length (), false));
- set_type_align (type, ctf_type_align (dict, tid));
+
+ if (ssize_t align = ctf_type_align (dict, tid);
+ align >= 0)
+ set_type_align (type, align);
+ else
+ complaint (_("ctf_type_align read_enum_type failed - %s"),
+ ctf_errmsg (ctf_errno (dict)));

return set_tid_type (objfile, tid, type);
}
@@ -814,7 +833,12 @@ read_array_type (struct ctf_context *ccp, ctf_id_t tid)
else
type->set_length (ctf_type_size (dict, tid));

- set_type_align (type, ctf_type_align (dict, tid));
+ if (ssize_t align = ctf_type_align (dict, tid);
+ align >= 0)
+ set_type_align (type, align);
+ else
+ complaint (_("ctf_type_align read_array_type failed - %s"),
+ ctf_errmsg (ctf_errno (dict)));

return set_tid_type (objfile, tid, type);
}
@@ -936,7 +960,13 @@ read_pointer_type (struct ctf_context *ccp, ctf_id_t tid, ctf_id_t btid)
}

type = lookup_pointer_type (target_type);
- set_type_align (type, ctf_type_align (ccp->dict, tid));
+
+ if (ssize_t align = ctf_type_align (ccp->dict, tid);
+ align >= 0)
+ set_type_align (type, align);
+ else
+ complaint (_("ctf_type_align read_pointer_type failed - %s"),
+ ctf_errmsg (ctf_errno (ccp->dict)));

return set_tid_type (objfile, tid, type);
}
--
2.53.0