5 files changed, 34 insertions, 1 deletions
diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog
index 6de6af5..17816a3 100644
--- a/gcc/c-family/ChangeLog
+++ b/gcc/c-family/ChangeLog
@@ -1,3 +1,8 @@
+2015-06-08  Marek Polacek  <polacek@redhat.com>
+
+	PR c/66415
+	* c-format.c (location_from_offset): Return LOC if LINE is null.
+
 2015-06-05  Aldy Hernandez  <aldyh@redhat.com>
 
 	* c-common.h (c_parse_final_cleanups): New prototype.
diff --git a/gcc/c-family/c-format.c b/gcc/c-family/c-format.c
index 719b3a9..564e47b 100644
--- a/gcc/c-family/c-format.c
+++ b/gcc/c-family/c-format.c
@@ -138,9 +138,11 @@ location_from_offset (location_t loc, int offset)
   expanded_location s = expand_location_to_spelling_point (loc);
   int line_width;
   const char *line = location_get_source_line (s, &line_width);
+  if (line == NULL)
+    return loc;
   line += s.column - 1 ;
   line_width -= s.column - 1;
-  unsigned int column = 
+  unsigned int column =
     location_column_from_byte_offset (line, line_width, (unsigned) offset);
 
   return linemap_position_for_loc_and_offset (line_table, loc, column);
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 5537a46..202551f 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2015-06-08  Marek Polacek  <polacek@redhat.com>
+
+	PR c/66415
+	* gcc.dg/cpp/pr66415-1.c: New test.
+	* gcc.dg/cpp/pr66415-2.c: New test.
+
 2015-06-08  Richard Biener  <rguenther@suse.de>
 
 	PR tree-optimization/66422
diff --git a/gcc/testsuite/gcc.dg/cpp/pr66415-1.c b/gcc/testsuite/gcc.dg/cpp/pr66415-1.c
new file mode 100644
index 0000000..922e326
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/pr66415-1.c
@@ -0,0 +1,9 @@
+/* PR c/66415 */
+/* { dg-do compile } */
+/* { dg-options "-Wformat" } */
+
+void
+fn1 (void)
+{
+  __builtin_printf                                ("xxxxxxxxxxxxxxxxx%dxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"); /* { dg-warning "format" } */
+}
diff --git a/gcc/testsuite/gcc.dg/cpp/pr66415-2.c b/gcc/testsuite/gcc.dg/cpp/pr66415-2.c
new file mode 100644
index 0000000..c168ce9
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/cpp/pr66415-2.c
@@ -0,0 +1,11 @@
+/* PR c/66415 */
+/* { dg-do compile } */
+/* { dg-options "-Wformat" } */
+
+#24
+void
+fn1 (void)
+{
+  __builtin_printf                                ("xxxxxxxxxxxxxxxxx%dxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx");
+  /* { dg-warning "format" "" { target *-*-* } 27 } */
+}