Hi,
as was figured out in PR LTO + ASan raises false initialization order
fiasco alarm due to in LTO case main_input_filename doesn't match module
name passed to __asan_before_dynamic_init.
Following Jakub's suggestion I used TRANSLATION_UNIT_DECL for
corresponding globals to overcome this issue (I needed to create a
source location for each TRANSLATION_UNIT_DECL).
However, when testing, I hit on a nasty issue: for some reason
linemap_ordinary_map_lookup, called from lto_output_location for given
TRANSLATION_UNIT_DECL, hit an assert:
[...]
linemap_assert (line >= MAP_START_LOCATION (result));
return result;
}
due to line == 2.
After some investigation I noticed that source locations are propagated
through location cache that can be partially invalidated by
lto_location_cache::revert_location_cache call. And that was my case:
after adding source location for TRANSLATION_UNIT_DECL into location
cache, it was reverted by calling
lto_location_cache::revert_location_cache from unify_scc before it was
accepted:
static void
lto_read_decls (struct lto_file_decl_data *decl_data, const void *data,
vec<ld_plugin_symbol_resolution_t> resolutions)
{
[...]
/* Try to unify the SCC with already existing ones. */
if (!flag_ltrans
&& unify_scc (data_in, from,
len, scc_entry_len, scc_hash))
continue;
For now I can overcome it by calling
location_cache.accept_location_cache for TRANSLATION_UNIT_DECL, but I
wonder if more reliable fix is possible.
Attached patch fixes the issue mentioned in PR and passes regression
testing and LTO bootstrap on x86_64-unknown-linux-gnu.
Could you please take a look on it?
-Maxim
gcc/lto/ChangeLog:
2017-01-17 Maxim Ostapenko <m.ostape...@samsung.com>
* lto.c (lto_read_decls): accept location cache for
TRANSLATION_UNIT_DECL.
gcc/testsuite/ChangeLog:
2017-01-17 Maxim Ostapenko <m.ostape...@samsung.com>
* gcc.dg/cpp/mi1.c: Adjust testcase.
* gcc.dg/pch/cpp-3.c: Likewise.
gcc/ChangeLog:
2017-01-17 Maxim Ostapenko <m.ostape...@samsung.com>
* asan.c (get_translation_unit_decl): New function.
(asan_add_global): Extract modules file name from globals
TRANSLATION_UNIT_DECL in lto mode.
* tree.c (build_translation_unit_decl): Add source location for newly
built TRANSLATION_UNIT_DECL.
diff --git a/gcc/asan.c b/gcc/asan.c
index 7450044..9a59fe4 100644
--- a/gcc/asan.c
+++ b/gcc/asan.c
@@ -2372,6 +2372,22 @@ asan_needs_odr_indicator_p (tree decl)
&& TREE_PUBLIC (decl));
}
+/* For given DECL return its corresponding TRANSLATION_UNIT_DECL. */
+
+static const_tree
+get_translation_unit_decl (tree decl)
+{
+ const_tree context = decl;
+ while (context && TREE_CODE (context) != TRANSLATION_UNIT_DECL)
+ {
+ if (TREE_CODE (context) == BLOCK)
+ context = BLOCK_SUPERCONTEXT (context);
+ else
+ context = get_containing_scope (context);
+ }
+ return context;
+}
+
/* Append description of a single global DECL into vector V.
TYPE is __asan_global struct type as returned by asan_global_struct. */
@@ -2391,7 +2407,14 @@ asan_add_global (tree decl, tree type, vec<constructor_elt, va_gc> *v)
pp_string (&asan_pp, "<unknown>");
str_cst = asan_pp_string (&asan_pp);
- pp_string (&module_name_pp, main_input_filename);
+ const char *filename = main_input_filename;
+ if (in_lto_p)
+ {
+ const_tree translation_unit_decl = get_translation_unit_decl (decl);
+ if (translation_unit_decl)
+ filename = DECL_SOURCE_FILE (translation_unit_decl);
+ }
+ pp_string (&module_name_pp, filename);
module_name_cst = asan_pp_string (&module_name_pp);
if (asan_needs_local_alias (decl))
diff --git a/gcc/lto/lto.c b/gcc/lto/lto.c
index d77d85d..c65e7cd 100644
--- a/gcc/lto/lto.c
+++ b/gcc/lto/lto.c
@@ -1707,7 +1707,13 @@ lto_read_decls (struct lto_file_decl_data *decl_data, const void *data,
&& (TREE_CODE (first) == IDENTIFIER_NODE
|| TREE_CODE (first) == INTEGER_CST
|| TREE_CODE (first) == TRANSLATION_UNIT_DECL))
- continue;
+ {
+ /* For TRANSLATION_UNIT_DECL we need to accept location cache now
+ to avoid possible reverting during following unify_scc call. */
+ if (TREE_CODE (first) == TRANSLATION_UNIT_DECL)
+ data_in->location_cache.accept_location_cache ();
+ continue;
+ }
/* Try to unify the SCC with already existing ones. */
if (!flag_ltrans
diff --git a/gcc/testsuite/gcc.dg/cpp/mi1.c b/gcc/testsuite/gcc.dg/cpp/mi1.c
index 0cfedad..9817431 100644
--- a/gcc/testsuite/gcc.dg/cpp/mi1.c
+++ b/gcc/testsuite/gcc.dg/cpp/mi1.c
@@ -13,7 +13,7 @@
/* { dg-do compile }
{ dg-options "-H" }
- { dg-message "mi1c\.h\n\[^\n\]*mi1cc\.h\n\[^\n\]*mi1nd\.h\n\[^\n\]*mi1ndp\.h\n\[^\n\]*mi1x\.h" "redundant include check" { target *-*-* } 0 } */
+ { dg-message "mi1c\.h\n\[^\n\]*mi1cc\.h\n\[^\n\]*mi1nd\.h\n\[^\n\]*mi1ndp\.h\n\[^\n\]*mi1x\.h\n\[^\n\]*mi1\.c" "redundant include check" { target *-*-* } 0 } */
#include "mi1c.h"
#include "mi1c.h"
diff --git a/gcc/testsuite/gcc.dg/pch/cpp-3.c b/gcc/testsuite/gcc.dg/pch/cpp-3.c
index 25b5ca4..d635706 100644
--- a/gcc/testsuite/gcc.dg/pch/cpp-3.c
+++ b/gcc/testsuite/gcc.dg/pch/cpp-3.c
@@ -1,7 +1,7 @@
/* PR preprocessor/36649 */
/* { dg-do compile } */
/* { dg-options "-H -I." } */
-/* { dg-message "cpp-3.h\[^\n\]*(\n\[^\n\]*cpp-3.c)?\n\[^\n\]*cpp-3a.h\n\[^\n\]*cpp-3b.h" "" { target *-*-* } 0 } */
+/* { dg-message "cpp-3.h\[^\n\]*(\n\[^\n\]*cpp-3.c)?\n\[^\n\]*cpp-3a.h\n\[^\n\]*cpp-3b.h\n\[^\n\]*cpp-3.c" "" { target *-*-* } 0 } */
#include "cpp-3.h"
#include "cpp-3a.h"
diff --git a/gcc/tree.c b/gcc/tree.c
index cffa36d..59fe8d4 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -4758,7 +4758,10 @@ vec<tree, va_gc> *all_translation_units;
tree
build_translation_unit_decl (tree name)
{
- tree tu = build_decl (UNKNOWN_LOCATION, TRANSLATION_UNIT_DECL,
+ linemap_add (line_table, LC_ENTER, false, main_input_filename, 1);
+ location_t loc = linemap_line_start (line_table, 1, 0);
+ linemap_add (line_table, LC_LEAVE, false, NULL, 0);
+ tree tu = build_decl (loc, TRANSLATION_UNIT_DECL,
name, NULL_TREE);
TRANSLATION_UNIT_LANGUAGE (tu) = lang_hooks.name;
vec_safe_push (all_translation_units, tu);
