解决ceil函数嵌套tan函数可能返回-0的问题

src/common/backend/utils/adt/float.cpp

@@ -1418,7 +1418,13 @@ Datum dceil(PG_FUNCTION_ARGS)
 {
     float8 arg1 = PG_GETARG_FLOAT8(0);
 
-    PG_RETURN_FLOAT8(ceil(arg1));
+    float8 result = ceil(arg1);
+    if (DB_IS_CMPT(A_FORMAT) && -0.0 == result) {
+        /* ceil function won't return -0 if compatible with O type database */
+        result = 0.0;
+    }
+
+    PG_RETURN_FLOAT8(result);
 }
 
 /*

src/test/regress/expected/ceil_negtive_zero.out

@@ -0,0 +1,43 @@
+--
+-- 处理ceil函数返回-0问题
+--
+create database ceil_nzero_test DBCOMPATIBILITY 'A';
+\c ceil_nzero_test
+select ceil(tan(-0.5));
+ ceil 
+------
+    0
+(1 row)
+
+\c postgres
+drop database ceil_nzero_test;
+create database ceil_nzero_test DBCOMPATIBILITY 'B';
+\c ceil_nzero_test
+select ceil(tan(-0.5));
+ ceil 
+------
+   -0
+(1 row)
+
+\c postgres
+drop database ceil_nzero_test;
+create database ceil_nzero_test DBCOMPATIBILITY 'C';
+\c ceil_nzero_test
+select ceil(tan(-0.5));
+ ceil 
+------
+   -0
+(1 row)
+
+\c postgres
+drop database ceil_nzero_test;
+create database ceil_nzero_test DBCOMPATIBILITY 'PG';
+\c ceil_nzero_test
+select ceil(tan(-0.5));
+ ceil 
+------
+   -0
+(1 row)
+
+\c postgres
+drop database ceil_nzero_test;

src/test/regress/parallel_schedule0

@@ -1028,6 +1028,9 @@ test: gsbasebackup_options
 test: gsdump_options
 test: gsloader_options
 
+# debug ceil(-0.5) -0
+test: ceil_negtive_zero
+
 # dolphin_guc_config
 test: dolphin_guc_config
 

src/test/regress/sql/ceil_negtive_zero.sql

@@ -0,0 +1,27 @@
+--
+-- 处理ceil函数返回-0问题
+--
+
+create database ceil_nzero_test DBCOMPATIBILITY 'A';
+\c ceil_nzero_test
+select ceil(tan(-0.5));
+\c postgres
+drop database ceil_nzero_test;
+
+create database ceil_nzero_test DBCOMPATIBILITY 'B';
+\c ceil_nzero_test
+select ceil(tan(-0.5));
+\c postgres
+drop database ceil_nzero_test;
+
+create database ceil_nzero_test DBCOMPATIBILITY 'C';
+\c ceil_nzero_test
+select ceil(tan(-0.5));
+\c postgres
+drop database ceil_nzero_test;
+
+create database ceil_nzero_test DBCOMPATIBILITY 'PG';
+\c ceil_nzero_test
+select ceil(tan(-0.5));
+\c postgres
+drop database ceil_nzero_test;