diff --git a/src/test/regress/expected/float8-exp-three-digits-win32.out b/src/test/regress/expected/float8-exp-three-digits-win32.out
index 2dd648d6b92..fe97af0029b 100644
--- a/src/test/regress/expected/float8-exp-three-digits-win32.out
+++ b/src/test/regress/expected/float8-exp-three-digits-win32.out
@@ -24,6 +24,25 @@ SELECT '-10e-400'::float8;
 ERROR:  "-10e-400" is out of range for type double precision
 LINE 1: SELECT '-10e-400'::float8;
                ^
+-- test whether denormalized values are accepted
+SELECT '4.95e-324'::float8 < '1.49e-323'::float8;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '4.95e-324'::float8 > '0'::float8;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT substr('-4.95e-324'::float8::text, 1, 4);
+ substr 
+--------
+ -4.9
+(1 row)
+
 -- bad input
 INSERT INTO FLOAT8_TBL(f1) VALUES ('');
 ERROR:  invalid input syntax for type double precision: ""
diff --git a/src/test/regress/expected/float8-small-is-zero.out b/src/test/regress/expected/float8-small-is-zero.out
index 5da743374c9..2bf2e6ce607 100644
--- a/src/test/regress/expected/float8-small-is-zero.out
+++ b/src/test/regress/expected/float8-small-is-zero.out
@@ -24,6 +24,25 @@ SELECT '10e-400'::float8;
 
 SELECT '-10e-400'::float8;
  float8 
+-- test whether denormalized values are accepted
+SELECT '4.95e-324'::float8 < '1.49e-323'::float8;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '4.95e-324'::float8 > '0'::float8;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT substr('-4.95e-324'::float8::text, 1, 4);
+ substr 
+--------
+ -4.9
+(1 row)
+
 --------
      -0
 (1 row)
diff --git a/src/test/regress/expected/float8-small-is-zero_1.out b/src/test/regress/expected/float8-small-is-zero_1.out
index 530842e1023..b276eeca4f2 100644
--- a/src/test/regress/expected/float8-small-is-zero_1.out
+++ b/src/test/regress/expected/float8-small-is-zero_1.out
@@ -24,6 +24,25 @@ SELECT '10e-400'::float8;
 
 SELECT '-10e-400'::float8;
  float8 
+-- test whether denormalized values are accepted
+SELECT '4.95e-324'::float8 < '1.49e-323'::float8;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '4.95e-324'::float8 > '0'::float8;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT substr('-4.95e-324'::float8::text, 1, 4);
+ substr 
+--------
+ -4.9
+(1 row)
+
 --------
       0
 (1 row)
diff --git a/src/test/regress/expected/float8.out b/src/test/regress/expected/float8.out
index 6221538af5c..df6ec9c58c7 100644
--- a/src/test/regress/expected/float8.out
+++ b/src/test/regress/expected/float8.out
@@ -24,6 +24,25 @@ SELECT '-10e-400'::float8;
 ERROR:  "-10e-400" is out of range for type double precision
 LINE 1: SELECT '-10e-400'::float8;
                ^
+-- test whether denormalized values are accepted
+SELECT '4.95e-324'::float8 < '1.49e-323'::float8;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT '4.95e-324'::float8 > '0'::float8;
+ ?column? 
+----------
+ t
+(1 row)
+
+SELECT substr('-4.95e-324'::float8::text, 1, 4);
+ substr 
+--------
+ -4.9
+(1 row)
+
 -- bad input
 INSERT INTO FLOAT8_TBL(f1) VALUES ('');
 ERROR:  invalid input syntax for type double precision: ""
diff --git a/src/test/regress/sql/float8.sql b/src/test/regress/sql/float8.sql
index 92a574ab7bf..1f24556fed4 100644
--- a/src/test/regress/sql/float8.sql
+++ b/src/test/regress/sql/float8.sql
@@ -16,6 +16,11 @@ SELECT '-10e400'::float8;
 SELECT '10e-400'::float8;
 SELECT '-10e-400'::float8;
 
+-- test whether denormalized values are accepted
+SELECT '4.95e-324'::float8 < '1.49e-323'::float8;
+SELECT '4.95e-324'::float8 > '0'::float8;
+SELECT substr('-4.95e-324'::float8::text, 1, 4);
+
 -- bad input
 INSERT INTO FLOAT8_TBL(f1) VALUES ('');
 INSERT INTO FLOAT8_TBL(f1) VALUES ('     ');