diff --git a/erpcgen/src/CGenerator.cpp b/erpcgen/src/CGenerator.cpp
index 16b86311..5bb5c8d0 100644
--- a/erpcgen/src/CGenerator.cpp
+++ b/erpcgen/src/CGenerator.cpp
@@ -765,6 +765,8 @@ void CGenerator::makeAliasesTemplateData()
             DataType *elementDataType = aliasType->getElementType();
             setTemplateComments(aliasType, aliasInfo);
 
+            aliasInfo["forwardDecl"] = "";
+
             if (elementDataType->getName() != "")
             {
                 string realType;
@@ -785,14 +787,18 @@ void CGenerator::makeAliasesTemplateData()
                 if (elementDataType->getName() == aliasType->getName() ||
                     getOutputName(elementDataType, false) == aliasType->getName())
                 {
+                    string forwardDecl;
                     if (elementDataType->isStruct())
                     {
                         realType = "struct " + realType;
+                        forwardDecl = "struct " + getOutputName(aliasType);
                     }
                     else
                     {
                         realType = "union " + realType;
+                        forwardDecl = "union " + getOutputName(aliasType);
                     }
+                    aliasInfo["forwardDecl"] = forwardDecl;
                 }
 
                 aliasInfo["typenameName"] = realType;
diff --git a/erpcgen/src/templates/c_common_header.template b/erpcgen/src/templates/c_common_header.template
index 9e203662..912ad3c0 100644
--- a/erpcgen/src/templates/c_common_header.template
+++ b/erpcgen/src/templates/c_common_header.template
@@ -40,6 +40,9 @@ extern "C"
 
 #if !defined(ERPC_TYPE_DEFINITIONS{$scopeNamePrefix}{$scopeNameC})
 #define ERPC_TYPE_DEFINITIONS{$scopeNamePrefix}{$scopeNameC}
+{% if not cCommonHeaderFile %}
+{$fillNamespaceBegin()}
+{% endif -- not cCommonHeaderFile %}
 {% if not empty(enums) %}
 
 // Enumerators data types declarations
@@ -67,6 +70,9 @@ typedef {$alias.unnamedType}
 {%    endfor -- alias.unnamed.members %}
 } {$alias.unnamedName};
 {%   else -- alias.typenameName %}
+{%    if alias.forwardDecl != "" %}
+{$alias.forwardDecl};
+{%    endif -- alias.forwardDecl %}
 typedef {$alias.typenameName};{$alias.ilComment}
 {%   endif -- alias.typenameName %}
 {%  endfor -- aliases %}
@@ -95,17 +101,24 @@ union {$us.name}
 {%    endif -- us.type == "union/struct" %}
 {%   endif -- !us.isExternal %}
 {%  endfor -- symbols %}
-
 {% endif -- nonExternalStruct || nonExternalUnion %}
 {% if not empty(consts) %}
 
 // Constant variable declarations
 {%  for c in consts %}
 {$> c.mlComment}
+{%   if cCommonHeaderFile %}
 extern const {$c.typeAndName};{$c.ilComment}{$loop.addNewLineIfNotLast}
+{%   else -- not cCommonHeaderFile %}
+constexpr {$c.typeAndName} = {$c.value};{$c.ilComment}{$loop.addNewLineIfNotLast}
+{%   endif -- cCommonHeaderFile %}
 {%  endfor -- consts %}
 {% endif -- consts %}
+{% if not cCommonHeaderFile %}
+
+{$fillNamespaceEnd()}
 
+{% endif -- not cCommonHeaderFile %}
 #endif // ERPC_TYPE_DEFINITIONS{$scopeNamePrefix}{$scopeNameC}
 
 {% if cCommonHeaderFile %}
diff --git a/install_dependencies.sh b/install_dependencies.sh
index ca3f79c1..14862cdb 100755
--- a/install_dependencies.sh
+++ b/install_dependencies.sh
@@ -25,10 +25,10 @@ Darwin*)
     brew update
     echo "Installing dependencies."
     brew install python3 bison flex -v -f 2>&1
-    sudo pip3 install tornado
-    sudo pip3 install --user nose
-    sudo pip3 install pytest --upgrade --ignore-installed six
-    sudo pip3 install pyyaml
+    sudo pip3 install --break-system-packages tornado
+    sudo pip3 install --break-system-packages --user nose
+    sudo pip3 install --break-system-packages pytest --upgrade --ignore-installed six
+    sudo pip3 install --break-system-packages pyyaml
     ;;
 *)
     echo "Unknown or currently unsupported os: ${unameOut}"