libdw: initialize state early in read_srclines

Starting with commit f8443bd09f8a8d3d84a63e5ce206a218e57dff7a,
we might jump to "out" on error before initialization of "state".
Initialize "state" early to fix this issue.

Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>

diff --git a/libdw/ChangeLog b/libdw/ChangeLog
index b344d92..5218145 100644 (file)
--- a/libdw/ChangeLog
+++ b/libdw/ChangeLog
@@ -1,3 +1,7 @@
+2015-10-16  Dmitry V. Levin  <ldv@altlinux.org>
+
+       * dwarf_getsrclines.c (read_srclines): Initialize state early.
+
 2015-10-13  Chih-Hung Hsieh  <chh@google.com>
 
        * dwarf_getsrclines.c (read_srclines): Move nested functions

diff --git a/libdw/dwarf_getsrclines.c b/libdw/dwarf_getsrclines.c
index 03bdc8f..dd1b3c1 100644 (file)
--- a/libdw/dwarf_getsrclines.c
+++ b/libdw/dwarf_getsrclines.c
@@ -185,6 +185,25 @@ read_srclines (Dwarf *dbg,
   struct dirlist dirstack[MAX_STACK_DIRS];
   struct dirlist *dirarray = dirstack;
 
+  /* We are about to process the statement program.  Initialize the
+     state machine registers (see 6.2.2 in the v2.1 specification).  */
+  struct line_state state =
+    {
+      .linelist = NULL,
+      .nlinelist = 0,
+      .addr = 0,
+      .op_index = 0,
+      .file = 1,
+      /* We only store int but want to check for overflow (see SET above).  */
+      .line = 1,
+      .column = 0,
+      .basic_block = false,
+      .prologue_end = false,
+      .epilogue_begin = false,
+      .isa = 0,
+      .discriminator = 0
+    };
+
   if (unlikely (linep + 4 > lineendp))
     {
     invalid_data:
@@ -387,25 +406,7 @@ read_srclines (Dwarf *dbg,
       goto out;
     }
 
-  /* We are about to process the statement program.  Initialize the
-     state machine registers (see 6.2.2 in the v2.1 specification).  */
-  struct line_state state =
-    {
-      .linelist = NULL,
-      .nlinelist = 0,
-      .addr = 0,
-      .op_index = 0,
-      .file = 1,
-      /* We only store int but want to check for overflow (see SET above).  */
-      .line = 1,
-      .column = 0,
-      .is_stmt = default_is_stmt,
-      .basic_block = false,
-      .prologue_end = false,
-      .epilogue_begin = false,
-      .isa = 0,
-      .discriminator = 0
-    };
+  state.is_stmt = default_is_stmt;
 
   /* Apply the "operation advance" from a special opcode or
      DW_LNS_advance_pc (as per DWARF4 6.2.5.1).  */