[binutils-gdb] Pass alignment when using GCC_C_FE_VERSION_2

[Tom Tromey <tromey@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=91e15dbaf9d05747fab0d33e5af7ae69c983398a

commit 91e15dbaf9d05747fab0d33e5af7ae69c983398a
Author: Tom Tromey <tom@tromey.com>
Date:   Wed Feb 21 08:22:01 2024 -0700

    Pass alignment when using GCC_C_FE_VERSION_2
    
    When the GCC compiler plugin responds with GCC_C_FE_VERSION_2, gdb can
    use the new 'finish_record_with_alignment' method.  This lets gdb pass
    alignment information to the compiler, which in turn fixes the test
    case included in this patch.
    
    Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31397

Diff:
---
 gdb/compile/compile-c-types.c         | 6 +++++-
 gdb/testsuite/gdb.compile/compile.c   | 7 +++++++
 gdb/testsuite/gdb.compile/compile.exp | 3 +++
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/gdb/compile/compile-c-types.c b/gdb/compile/compile-c-types.c
index 1bfaefc4933..1243be369f8 100644
--- a/gdb/compile/compile-c-types.c
+++ b/gdb/compile/compile-c-types.c
@@ -118,7 +118,11 @@ convert_struct_or_union (compile_c_instance *context, struct type *type)
 					  type->field (i).loc_bitpos ());
     }
 
-  context->plugin ().finish_record_or_union (result, type->length ());
+  if (context->plugin ().version () >= GCC_C_FE_VERSION_2)
+    context->plugin ().finish_record_with_alignment (result, type->length (),
+						     type_align (type));
+  else
+    context->plugin ().finish_record_or_union (result, type->length ());
   return result;
 }
 
diff --git a/gdb/testsuite/gdb.compile/compile.c b/gdb/testsuite/gdb.compile/compile.c
index 8170a3af5ab..04beae823c8 100644
--- a/gdb/testsuite/gdb.compile/compile.c
+++ b/gdb/testsuite/gdb.compile/compile.c
@@ -100,6 +100,13 @@ int globalshadow = 10;
 static int staticshadow = 20;
 int externed = 7;
 
+struct struct_with_array
+{
+  char val[7];
+};
+
+static struct struct_with_array swa;
+
 int
 main (void)
 {
diff --git a/gdb/testsuite/gdb.compile/compile.exp b/gdb/testsuite/gdb.compile/compile.exp
index fed7b04a4c3..f522a84d5dd 100644
--- a/gdb/testsuite/gdb.compile/compile.exp
+++ b/gdb/testsuite/gdb.compile/compile.exp
@@ -397,3 +397,6 @@ gdb_test "p globalvar" " = 1" "expect 1"
 
 gdb_test_no_output "compile code shlibvar += 5;" "modify shared library variable"
 gdb_test "p shlibvar" " = 15" "expect 15"
+
+# This used to fail due to alignment.  PR compile/31397.
+gdb_test_no_output "compile code swa.val\[0\] = 1"