Merge amd64.(none):/src/rel_clean_up/my50-rel_clean_up

into  amd64.(none):/src/rel_clean_up/my51-rel_clean_up


mysql-test/r/type_decimal.result:
  Auto merged
mysql-test/t/type_decimal.test:
  Auto merged
sql/my_decimal.h:
  Auto merged

1 files changed, 11 insertions, 2 deletions

diff --git a/sql/my_decimal.h b/sql/my_decimal.h
index 1885036f42b..e73e0d4080d 100644
--- a/sql/my_decimal.h
+++ b/sql/my_decimal.h
@@ -169,14 +169,23 @@ inline int check_result_and_overflow(uint mask, int result, my_decimal *val)
 inline uint my_decimal_length_to_precision(uint length, uint scale,
                                            bool unsigned_flag)
 {
-  return (uint) (length - (scale>0 ? 1:0) - (unsigned_flag ? 0:1));
+  /* Precision can't be negative thus ignore unsigned_flag when length is 0. */
+  DBUG_ASSERT(length || !scale);
+  return (uint) (length - (scale>0 ? 1:0) -
+                 (unsigned_flag || !length ? 0:1));
 }
 
 inline uint32 my_decimal_precision_to_length(uint precision, uint8 scale,
                                              bool unsigned_flag)
 {
+  /*
+    When precision is 0 it means that original length was also 0. Thus
+    unsigned_flag is ignored in this case.
+  */
+  DBUG_ASSERT(precision || !scale);
   set_if_smaller(precision, DECIMAL_MAX_PRECISION);
-  return (uint32)(precision + (scale>0 ? 1:0) + (unsigned_flag ? 0:1));
+  return (uint32)(precision + (scale>0 ? 1:0) +
+                  (unsigned_flag || !precision ? 0:1));
 }
 
 inline