Fix warnings

Author: isuruf

ext/symengine/ruby_basic.c

@@ -132,7 +132,7 @@ VALUE cbasic_get_args(VALUE self) {
     size = vecbasic_size(args);
     VALUE ruby_array = rb_ary_new2(size);
     int i = 0;
-    VALUE temp = NULL;
+    VALUE temp;
     for(i = 0; i < size; i++) {
         basic_struct *temp_basic = basic_new_heap();
         vecbasic_get(args, i, temp_basic);
@@ -154,7 +154,7 @@ VALUE cbasic_free_symbols(VALUE self) {
     size = setbasic_size(symbols);
     VALUE ruby_array = rb_ary_new2(size);
     int i = 0;
-    VALUE temp = NULL;
+    VALUE temp;
     for(i = 0; i < size; i++) {
         basic_struct *temp_basic = basic_new_heap();
         setbasic_get(symbols, i, temp_basic);

ext/symengine/ruby_real_mpfr.c

@@ -20,8 +20,7 @@ VALUE crealmpfr_init(VALUE self, VALUE num_value, VALUE prec_value)
             real_mpfr_set_str(cresult, c, prec);
             break;
         case T_DATA:
-            c = rb_obj_classname(num_value);
-            if (strcmp(c, "BigDecimal") == 0) {
+            if (strcmp(rb_obj_classname(num_value), "BigDecimal") == 0) {
                 c = RSTRING_PTR(rb_funcall(num_value, rb_intern("to_s"), 1, rb_str_new2("F")));
                 real_mpfr_set_str(cresult, c, prec);
                 break;

ext/symengine/ruby_symbol.c

@@ -1,17 +1,17 @@
 #include "ruby_symbol.h"
 
 VALUE csymbol_init(VALUE self, VALUE name_or_id) {
-    char *str_ptr;
+    const char *str_ptr;
 
     switch (TYPE(name_or_id)) {
-    case T_STRING:
-      str_ptr = StringValueCStr(name_or_id);
-      break;
-    case T_SYMBOL:
-      str_ptr = rb_id2name(rb_to_id(name_or_id));
-      break;      
-    default:
-      rb_raise(rb_eTypeError, "wrong argument type %s (expected Symbol or String)", rb_obj_classname(name_or_id));
+        case T_STRING:
+            str_ptr = StringValueCStr(name_or_id);
+            break;
+        case T_SYMBOL:
+            str_ptr = rb_id2name(rb_to_id(name_or_id));
+            break;      
+        default:
+            rb_raise(rb_eTypeError, "wrong argument type %s (expected Symbol or String)", rb_obj_classname(name_or_id));
     }
 
     basic_struct *this;

ext/symengine/symengine_utils.c

@@ -60,9 +60,8 @@ void sympify(VALUE operand2, basic_struct *cbasic_operand2) {
             break;
 
         case T_DATA:
-            c = rb_obj_classname(operand2);
             #ifdef HAVE_SYMENGINE_MPFR
-            if (strcmp(c, "BigDecimal") == 0) {
+            if (strcmp(rb_obj_classname(operand2), "BigDecimal") == 0) {
                 c = RSTRING_PTR( rb_funcall(operand2, rb_intern("to_s"), 1, rb_str_new2("F")) );
                 real_mpfr_set_str(cbasic_operand2, c, 200);
                 break;