BUG: wrapper generators were failing if hints file was not set

CMake/vtkWrapPython.cmake

@@ -72,6 +72,12 @@ MACRO(VTK_WRAP_PYTHON3 TARGET SRC_LIST_NAME SOURCES)
         SET(TMP_SPECIAL "--vtkobject")
       ENDIF (TMP_WRAP_SPECIAL)
 
+      IF (VTK_WRAP_HINTS)
+        SET(TMP_HINTS "--hints" "${quote}${VTK_WRAP_HINTS}${quote}")
+      ELSE (VTK_WRAP_HINTS)
+        SET(TMP_HINTS)
+      ENDIF (VTK_WRAP_HINTS)
+
       # add the info to the init file
       SET(VTK_WRAPPER_INIT_DATA
         "${VTK_WRAPPER_INIT_DATA}\n${TMP_FILENAME}")
@@ -88,7 +94,7 @@ MACRO(VTK_WRAP_PYTHON3 TARGET SRC_LIST_NAME SOURCES)
         ARGS
         ${TMP_CONCRETE}
         ${TMP_SPECIAL}
-        "--hints" "${quote}${VTK_WRAP_HINTS}${quote}"
+        ${TMP_HINTS}
         "${quote}${TMP_INPUT}${quote}"
         "${quote}${CMAKE_CURRENT_BINARY_DIR}/${TMP_FILENAME}Python.cxx${quote}"
         COMMENT "Python Wrapping - generating ${TMP_FILENAME}Python.cxx"

Wrapping/vtkParse.tab.c

@@ -5999,10 +5999,13 @@ int main(int argc, char *argv[])
     data.IsConcrete = atoi(argv[argi++]);
     }
 
-  if (!(fhint = fopen(hintFileName, "r")))
+  if (hintFileName && hintFileName[0] != '\0')
     {
-    fprintf(stderr, "Error opening hint file %s\n", hintFileName);
-    exit(1);
+    if (!(fhint = fopen(hintFileName, "r")))
+      {
+      fprintf(stderr, "Error opening hint file %s\n", hintFileName);
+      exit(1);
+      }
     }
 
   yyin = fin;

Wrapping/vtkParse.y

@@ -2075,10 +2075,13 @@ int main(int argc, char *argv[])
     data.IsConcrete = atoi(argv[argi++]);
     }
 
-  if (!(fhint = fopen(hintFileName, "r")))
+  if (hintFileName && hintFileName[0] != '\0')
     {
-    fprintf(stderr, "Error opening hint file %s\n", hintFileName);
-    exit(1);
+    if (!(fhint = fopen(hintFileName, "r")))
+      {
+      fprintf(stderr, "Error opening hint file %s\n", hintFileName);
+      exit(1);
+      }
     }
 
   yyin = fin;