diff --git a/Zend/zend.c b/Zend/zend.c
index 0eec5f89019..99d3cc02709 100644
--- a/Zend/zend.c
+++ b/Zend/zend.c
@@ -36,6 +36,7 @@
 #include "zend_observer.h"
 #include "zend_fibers.h"
 #include "zend_call_stack.h"
+#include "zend_strtod.h"
 #include "Optimizer/zend_optimizer.h"
 
 static size_t global_map_ptr_last = 0;
diff --git a/Zend/zend_operators.c b/Zend/zend_operators.c
index afe068bfeb8..e3b899c2b5d 100644
--- a/Zend/zend_operators.c
+++ b/Zend/zend_operators.c
@@ -18,18 +18,20 @@
    +----------------------------------------------------------------------+
 */
 
-#include <ctype.h>
-
-#include "zend.h"
 #include "zend_operators.h"
+#include "zend.h"
 #include "zend_variables.h"
+#include "zend_objects.h" // for zend_objects_new()
 #include "zend_globals.h"
+#include "zend_multiply.h" // for ZEND_SIGNED_MULTIPLY_LONG()
 #include "zend_list.h"
 #include "zend_API.h"
 #include "zend_strtod.h"
 #include "zend_exceptions.h"
 #include "zend_closures.h"
 
+#include <ctype.h>
+
 #include <locale.h>
 #ifdef HAVE_LANGINFO_H
 # include <langinfo.h>
diff --git a/Zend/zend_operators.h b/Zend/zend_operators.h
index 506c27fc50e..f448c7bd567 100644
--- a/Zend/zend_operators.h
+++ b/Zend/zend_operators.h
@@ -21,20 +21,19 @@
 #ifndef ZEND_OPERATORS_H
 #define ZEND_OPERATORS_H
 
-#include <errno.h>
+#include "zend_hash.h" // for zend_hash_num_elements()
+#include "zend_object_handlers.h" // for struct _zend_object_handlers
+#include "zend_portability.h" // for BEGIN_EXTERN_
+#include "zend_types.h" // for zend_result
+#include "zend_string.h" // for zend_string_copy()
+
 #include <math.h>
-#include <assert.h>
 #include <stddef.h>
 
 #ifdef HAVE_IEEEFP_H
 #include <ieeefp.h>
 #endif
 
-#include "zend_portability.h"
-#include "zend_strtod.h"
-#include "zend_multiply.h"
-#include "zend_object_handlers.h"
-
 #define LONG_SIGN_MASK ZEND_LONG_MIN
 
 BEGIN_EXTERN_C()
diff --git a/Zend/zend_variables.c b/Zend/zend_variables.c
index 06483d581df..69cb54dbc7d 100644
--- a/Zend/zend_variables.c
+++ b/Zend/zend_variables.c
@@ -18,7 +18,7 @@
    +----------------------------------------------------------------------+
 */
 
-#include <stdio.h>
+#include "zend_variables.h"
 #include "zend.h"
 #include "zend_API.h"
 #include "zend_ast.h"
diff --git a/Zend/zend_variables.h b/Zend/zend_variables.h
index ea3fd9c5efc..c07fdfe7acf 100644
--- a/Zend/zend_variables.h
+++ b/Zend/zend_variables.h
@@ -21,6 +21,7 @@
 #ifndef ZEND_VARIABLES_H
 #define ZEND_VARIABLES_H
 
+#include "zend_hash.h" // for zend_array_dup()
 #include "zend_types.h"
 #include "zend_gc.h"