Changed the default hierachy delimiter ('\0' -> '/') in dbBlock and dbLib classes.

This can resolve the following Coverage test fails.

[2025-08-21T08:03:50.795Z] The following tests FAILED:
[2025-08-21T08:03:50.795Z] 	153 - odb.cpp_tests.tcl (Failed)                        IntegrationTest tcl odb passfail
[2025-08-21T08:03:50.795Z] 	237 - TestHconn.ConnectionMade (Subprocess aborted)

Signed-off-by: Jaehyun Kim <[email protected]>

Author: jhkim-pii

src/cts/test/balance_levels.defok

@@ -1,5 +1,5 @@
 VERSION 5.8 ;
-DIVIDERCHAR "|" ;
+DIVIDERCHAR "/" ;
 BUSBITCHARS "[]" ;
 DESIGN multi_sink ;
 UNITS DISTANCE MICRONS 2000 ;

src/gpl/test/clust02.defok

@@ -1,5 +1,5 @@
 VERSION 5.8 ;
-DIVIDERCHAR "|" ;
+DIVIDERCHAR "/" ;
 BUSBITCHARS "[]" ;
 DESIGN top ;
 UNITS DISTANCE MICRONS 1000 ;

src/odb/include/odb/db.h

@@ -1330,7 +1330,7 @@ class dbBlock : public dbObject
   static dbBlock* create(dbChip* chip,
                          const char* name,
                          dbTech* tech = nullptr,
-                         char hier_delimiter = 0);
+                         char hier_delimiter = '/');
 
   ///
   /// Create a hierachical/child block. This block has no connectivity.
@@ -1340,7 +1340,7 @@ class dbBlock : public dbObject
   static dbBlock* create(dbBlock* block,
                          const char* name,
                          dbTech* tech = nullptr,
-                         char hier_delimiter = 0);
+                         char hier_delimiter = '/');
 
   ///
   /// Translate a database-id back to a pointer.
@@ -4990,7 +4990,7 @@ class dbLib : public dbObject
   static dbLib* create(dbDatabase* db,
                        const char* name,
                        dbTech* tech,
-                       char hierarchy_delimiter = 0);
+                       char hierarchy_delimiter = '/');
 
   ///
   /// Translate a database-id back to a pointer.

src/odb/src/db/dbBlock.cpp

@@ -152,7 +152,7 @@ _dbBlock::_dbBlock(_dbDatabase* db)
   _flags._spare_bits = 0;
   _def_units = 100;
   _dbu_per_micron = 1000;
-  _hier_delimiter = 0;
+  _hier_delimiter = '/';
   _left_bus_delimiter = 0;
   _right_bus_delimiter = 0;
   _num_ext_corners = 0;

src/odb/src/db/dbLib.cpp

@@ -98,7 +98,7 @@ _dbLib::_dbLib(_dbDatabase* db)
 {
   _lef_units = 0;
   _dbu_per_micron = 1000;
-  _hier_delimiter = 0;
+  _hier_delimiter = '/';
   _left_bus_delimiter = 0;
   _right_bus_delimiter = 0;
   _spare = 0;

src/rsz/test/buffer_varying_lengths.defok

@@ -1,5 +1,5 @@
 VERSION 5.8 ;
-DIVIDERCHAR "|" ;
+DIVIDERCHAR "/" ;
 BUSBITCHARS "[]" ;
 DESIGN top ;
 UNITS DISTANCE MICRONS 2000 ;