2 files changed, 127 insertions, 0 deletions
diff --git a/src/test/regress/expected/numeric.out b/src/test/regress/expected/numeric.out
index 72f03c8a38a..f30ac236f52 100644
--- a/src/test/regress/expected/numeric.out
+++ b/src/test/regress/expected/numeric.out
@@ -1346,6 +1346,108 @@ FROM generate_series(-5,5) AS t(i);
    5 |  -300000 |  -200000 |  -100000 |  100000 |  200000 |  300000
 (11 rows)
 
+-- Check limits of rounding before the decimal point
+SELECT round(4.4e131071, -131071) = 4e131071;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT round(4.5e131071, -131071) = 5e131071;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT round(4.5e131071, -131072); -- loses all digits
+ round 
+-------
+     0
+(1 row)
+
+SELECT round(5.5e131071, -131072); -- rounds up and overflows
+ERROR:  value overflows numeric format
+SELECT round(5.5e131071, -131073); -- loses all digits
+ round 
+-------
+     0
+(1 row)
+
+SELECT round(5.5e131071, -1000000); -- loses all digits
+ round 
+-------
+     0
+(1 row)
+
+-- Check limits of rounding after the decimal point
+SELECT round(5e-16383, 1000000) = 5e-16383;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT round(5e-16383, 16383) = 5e-16383;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT round(5e-16383, 16382) = 1e-16382;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT round(5e-16383, 16381) = 0;
+ ?column? 
+----------
+ t
+(1 row)
+
+-- Check limits of trunc() before the decimal point
+SELECT trunc(9.9e131071, -131071) = 9e131071;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT trunc(9.9e131071, -131072); -- loses all digits
+ trunc 
+-------
+     0
+(1 row)
+
+SELECT trunc(9.9e131071, -131073);  -- loses all digits
+ trunc 
+-------
+     0
+(1 row)
+
+SELECT trunc(9.9e131071, -1000000);  -- loses all digits
+ trunc 
+-------
+     0
+(1 row)
+
+-- Check limits of trunc() after the decimal point
+SELECT trunc(5e-16383, 1000000) = 5e-16383;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT trunc(5e-16383, 16383) = 5e-16383;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT trunc(5e-16383, 16382) = 0;
+ ?column? 
+----------
+ t
+(1 row)
+
 -- Testing for width_bucket(). For convenience, we test both the
 -- numeric and float8 versions of the function in this file.
 -- errors
diff --git a/src/test/regress/sql/numeric.sql b/src/test/regress/sql/numeric.sql
index 83fc386333b..c86395209ab 100644
--- a/src/test/regress/sql/numeric.sql
+++ b/src/test/regress/sql/numeric.sql
@@ -833,6 +833,31 @@ SELECT i as pow,
 	round((2.5 * 10 ^ i)::numeric, -i)
 FROM generate_series(-5,5) AS t(i);
 
+-- Check limits of rounding before the decimal point
+SELECT round(4.4e131071, -131071) = 4e131071;
+SELECT round(4.5e131071, -131071) = 5e131071;
+SELECT round(4.5e131071, -131072); -- loses all digits
+SELECT round(5.5e131071, -131072); -- rounds up and overflows
+SELECT round(5.5e131071, -131073); -- loses all digits
+SELECT round(5.5e131071, -1000000); -- loses all digits
+
+-- Check limits of rounding after the decimal point
+SELECT round(5e-16383, 1000000) = 5e-16383;
+SELECT round(5e-16383, 16383) = 5e-16383;
+SELECT round(5e-16383, 16382) = 1e-16382;
+SELECT round(5e-16383, 16381) = 0;
+
+-- Check limits of trunc() before the decimal point
+SELECT trunc(9.9e131071, -131071) = 9e131071;
+SELECT trunc(9.9e131071, -131072); -- loses all digits
+SELECT trunc(9.9e131071, -131073);  -- loses all digits
+SELECT trunc(9.9e131071, -1000000);  -- loses all digits
+
+-- Check limits of trunc() after the decimal point
+SELECT trunc(5e-16383, 1000000) = 5e-16383;
+SELECT trunc(5e-16383, 16383) = 5e-16383;
+SELECT trunc(5e-16383, 16382) = 0;
+
 -- Testing for width_bucket(). For convenience, we test both the
 -- numeric and float8 versions of the function in this file.