The following fixes #pragma pack effect leaking to all types built
from the middle-end (so possibly even vector types built by the
vectorizer?). The PR in question is about gcov_info_type where
layout is affected and inconsistency between that and the libgcov.a
copy causes libgcov to crash.
As the way to communicate #pragma pack to stor-layout.c is already
a hack I couldn't think of a better solution like that below.
Bootstrap and regtest running on x86_64-unknown-linux-gnu.
Ok?
Thanks,
Richard.
2015-07-08 Richard Biener <rguent...@suse.de>
* stor-layout.h (reset_maximum_field_alignment): Declare.
* stor-layout.c (reset_maximum_field_alignment): New function.
* toplev.c: Include stor-layout.h.
(compile_file): Reset maximum_field_alignment after parsing.
Index: gcc/stor-layout.c
===================================================================
--- gcc/stor-layout.c (revision 225534)
+++ gcc/stor-layout.c (working copy)
@@ -59,6 +59,12 @@ tree sizetype_tab[(int) stk_type_kind_la
The value is measured in bits. */
unsigned int maximum_field_alignment = TARGET_DEFAULT_PACK_STRUCT *
BITS_PER_UNIT;
+void
+reset_maximum_field_alignment (void)
+{
+ maximum_field_alignment = TARGET_DEFAULT_PACK_STRUCT * BITS_PER_UNIT;
+}
+
/* Nonzero if all REFERENCE_TYPEs are internal and hence should be allocated
in the address spaces' address_mode, not pointer_mode. Set only by
internal_reference_types called only by a front end. */
Index: gcc/stor-layout.h
===================================================================
--- gcc/stor-layout.h (revision 225534)
+++ gcc/stor-layout.h (working copy)
@@ -118,4 +118,7 @@ extern tree variable_size (tree);
/* Vector types need to check target flags to determine type. */
extern machine_mode vector_type_mode (const_tree);
+/* Reset maximum_field_alignment to its default. */
+extern void reset_maximum_field_alignment (void);
+
#endif // GCC_STOR_LAYOUT_H
Index: gcc/toplev.c
===================================================================
--- gcc/toplev.c (revision 225534)
+++ gcc/toplev.c (working copy)
@@ -90,6 +90,7 @@ along with GCC; see the file COPYING3.
#include "optabs.h"
#include "tree-chkp.h"
#include "omp-low.h"
+#include "stor-layout.h"
#if defined(DBX_DEBUGGING_INFO) || defined(XCOFF_DEBUGGING_INFO)
#include "dbxout.h"
@@ -553,6 +554,11 @@ compile_file (void)
if (flag_syntax_only || flag_wpa)
return;
+
+ /* Reset maximum_field_alignment, it can be adjusted by #pragma pack
+ and this shouldn't influence any types built by the middle-end
+ from now on (like gcov_info_type). */
+ reset_maximum_field_alignment ();
ggc_protect_identifiers = false;
