[binutils-gdb] Fix crash in amd64-tdep.c

[binutils-gdb] Fix crash in amd64-tdep.c

[Tom Tromey]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=862ebb27bbe30768356776a10827dd1c0824d405

commit 862ebb27bbe30768356776a10827dd1c0824d405
Author: Tom Tromey <tromey@adacore.com>
Date:   Tue Sep 6 08:44:52 2022 -0600

    Fix crash in amd64-tdep.c
    
    amd64-tdep.c could crash when 'finish'ing from a function whose return
    type had variable length.  In this situation, the value will be passed
    by reference, and this patch avoids the crash.
    
    (Note that this does not fully fix the bug reported, but it does fix
    the crash, so it seems worthwhile to land independently.)

Diff:
---
 gdb/amd64-tdep.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/gdb/amd64-tdep.c b/gdb/amd64-tdep.c
index b8cd8188044..0f2dab8b479 100644
--- a/gdb/amd64-tdep.c
+++ b/gdb/amd64-tdep.c
@@ -666,7 +666,8 @@ amd64_classify_aggregate (struct type *type, enum amd64_reg_class theclass[2])
 	loc_bitpos attributes, which will cause an assert to trigger within
 	the unaligned field check.  As classes with virtual bases are not
 	trivially copyable, checking that first avoids this problem.  */
-  if (type->length () > 16
+  if (TYPE_HAS_DYNAMIC_LENGTH (type)
+      || type->length () > 16
       || !language_pass_by_reference (type).trivially_copyable
       || amd64_has_unaligned_fields (type))
     {