With CFLAGS='-Og -g', F21 gcc hits -Werror=maybe-uninitialized in
read_encoded_value at "*result += value".  It's fine with -O2/-O0.

In particular it seems to care about the __libdw_cfi_read_address_inc
calls.  By my inspection, the only way those don't set value are for
error cases, which will then return immediately.  This patch just sets
value = 0 to begin with, so gcc is always convinced it's fine.

Signed-off-by: Josh Stone <[email protected]>
---
 libdw/ChangeLog       | 4 ++++
 libdw/encoded-value.h | 2 +-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/libdw/ChangeLog b/libdw/ChangeLog
index d377937ff57c..b6ad425d8640 100644
--- a/libdw/ChangeLog
+++ b/libdw/ChangeLog
@@ -1,3 +1,7 @@
+2015-02-11  Josh Stone  <[email protected]>
+
+       * encoded-value.h (read_encoded_value): Initialize value.
+
 2014-12-24  Mark Wielaard  <[email protected]>
 
        * dwarf_getsrc_die.c (dwarf_getsrc_die): Return the last line record
diff --git a/libdw/encoded-value.h b/libdw/encoded-value.h
index f953f5ef2a5f..0fa201835c5e 100644
--- a/libdw/encoded-value.h
+++ b/libdw/encoded-value.h
@@ -152,7 +152,7 @@ read_encoded_value (const Dwarf_CFI *cache, uint8_t 
encoding,
       return true;
     }
 
-  Dwarf_Addr value;
+  Dwarf_Addr value = 0;
   const unsigned char *endp = cache->data->d.d_buf + cache->data->d.d_size;
   switch (encoding & 0x0f)
     {
-- 
2.1.0

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