Re: GCC 7 backport

[Martin Liška <mliska at suse dot cz>]

Hi.

Another 2 patches that I've just tested.

Thanks,
Martin

>From a4ec4d12444bc2fed3fbf559d6cae4618caab7c8 Mon Sep 17 00:00:00 2001
From: marxin <marxin@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Mon, 18 Feb 2019 09:46:19 +0000
Subject: [PATCH 2/2] Backport r268981

libcpp/ChangeLog:

2019-02-18  Martin Liska  <mliska@suse.cz>

	PR c++/89383
	* line-map.c (linemap_line_start): Use 1UL in order
	to not overflow.
---
 libcpp/line-map.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/libcpp/line-map.c b/libcpp/line-map.c
index 5827f303b6d..ddcb0111f4b 100644
--- a/libcpp/line-map.c
+++ b/libcpp/line-map.c
@@ -756,7 +756,8 @@ linemap_line_start (struct line_maps *set, linenum_type to_line,
 	  || ( /* We can't reuse the map if the line offset is sufficiently
 		  large to cause overflow when computing location_t values.  */
 	      (to_line - ORDINARY_MAP_STARTING_LINE_NUMBER (map))
-	      >= (1U << (CHAR_BIT * sizeof (linenum_type) - column_bits)))
+	      >= (((uint64_t) 1)
+		  << (CHAR_BIT * sizeof (linenum_type) - column_bits)))
 	  || range_bits < map->m_range_bits)
 	map = linemap_check_ordinary
 	        (const_cast <line_map *>
-- 
2.21.0

>From c4a45a0f56b8eb91295260332989382180418506 Mon Sep 17 00:00:00 2001
From: dmalcolm <dmalcolm@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Tue, 12 Feb 2019 01:09:31 +0000
Subject: [PATCH 1/2] Backport r268789

gcc/ChangeLog:

2019-02-11  David Malcolm  <dmalcolm@redhat.com>

	PR lto/88147
	* input.c (selftest::test_line_offset_overflow): New selftest.
	(selftest::input_c_tests): Call it.

libcpp/ChangeLog:

2019-02-11  Martin Liska  <mliska@suse.cz>

	PR lto/88147
	* line-map.c (linemap_line_start): Don't reuse the existing line
	map if the line offset is sufficiently large to cause overflow
	when computing location_t values.
---
 gcc/input.c       | 30 ++++++++++++++++++++++++++++++
 libcpp/line-map.c |  4 ++++
 2 files changed, 34 insertions(+)

diff --git a/gcc/input.c b/gcc/input.c
index 80718100d0c..6412d70f4e2 100644
--- a/gcc/input.c
+++ b/gcc/input.c
@@ -3480,6 +3480,34 @@ for_each_line_table_case (void (*testcase) (const line_table_case &))
   ASSERT_EQ (num_cases_tested, 2 * 12);
 }
 
+/* Verify that when presented with a consecutive pair of locations with
+   a very large line offset, we don't attempt to consolidate them into
+   a single ordinary linemap where the line offsets within the line map
+   would lead to overflow (PR lto/88147).  */
+
+static void
+test_line_offset_overflow ()
+{
+  line_table_test ltt (line_table_case (5, 0));
+
+  linemap_add (line_table, LC_ENTER, false, "foo.c", 0);
+  linemap_line_start (line_table, 1, 100);
+  location_t loc_a = linemap_line_start (line_table, 2578, 255);
+  assert_loceq ("foo.c", 2578, 0, loc_a);
+
+  const line_map_ordinary *ordmap_a = LINEMAPS_LAST_ORDINARY_MAP (line_table);
+  ASSERT_EQ (ordmap_a->m_column_and_range_bits, 13);
+  ASSERT_EQ (ordmap_a->m_range_bits, 5);
+
+  location_t loc_b = linemap_line_start (line_table, 404198, 512);
+  assert_loceq ("foo.c", 404198, 0, loc_b);
+
+  /* We should have started a new linemap, rather than attempting to store
+     a very large line offset.  */
+  const line_map_ordinary *ordmap_b = LINEMAPS_LAST_ORDINARY_MAP (line_table);
+  ASSERT_NE (ordmap_a, ordmap_b);
+}
+
 /* Run all of the selftests within this file.  */
 
 void
@@ -3518,6 +3546,8 @@ input_c_tests ()
   for_each_line_table_case (test_lexer_char_constants);
 
   test_reading_source_line ();
+
+  test_line_offset_overflow ();
 }
 
 } // namespace selftest
diff --git a/libcpp/line-map.c b/libcpp/line-map.c
index 949489eb1a1..5827f303b6d 100644
--- a/libcpp/line-map.c
+++ b/libcpp/line-map.c
@@ -753,6 +753,10 @@ linemap_line_start (struct line_maps *set, linenum_type to_line,
       if (line_delta < 0
 	  || last_line != ORDINARY_MAP_STARTING_LINE_NUMBER (map)
 	  || SOURCE_COLUMN (map, highest) >= (1U << (column_bits - range_bits))
+	  || ( /* We can't reuse the map if the line offset is sufficiently
+		  large to cause overflow when computing location_t values.  */
+	      (to_line - ORDINARY_MAP_STARTING_LINE_NUMBER (map))
+	      >= (1U << (CHAR_BIT * sizeof (linenum_type) - column_bits)))
 	  || range_bits < map->m_range_bits)
 	map = linemap_check_ordinary
 	        (const_cast <line_map *>
-- 
2.21.0