diff --git a/cmake/macros/PackageConfig.cmake b/cmake/macros/PackageConfig.cmake
index 03fb49ff2f..8c1cf70ee5 100644
--- a/cmake/macros/PackageConfig.cmake
+++ b/cmake/macros/PackageConfig.cmake
@@ -301,10 +301,10 @@ function(export_packages filename)
   set(exports "# Exports for Panda3D PKG:: packages\n")
 
   foreach(pkg ${_ALL_PACKAGE_OPTIONS})
-    string(APPEND exports "\n# Create imported target PKG::${pkg}\n")
-    string(APPEND exports "add_library(PKG::${pkg} INTERFACE IMPORTED)\n\n")
+    set(exports "${exports}\n# Create imported target PKG::${pkg}\n")
+    set(exports "${exports}add_library(PKG::${pkg} INTERFACE IMPORTED)\n\n")
 
-    string(APPEND exports "set_target_properties(PKG::${pkg} PROPERTIES\n")
+    set(exports "${exports}set_target_properties(PKG::${pkg} PROPERTIES\n")
     foreach(prop
         INTERFACE_COMPILE_DEFINITIONS
         INTERFACE_COMPILE_FEATURES
@@ -318,7 +318,7 @@ function(export_packages filename)
         INTERFACE_SOURCES)
 
       set(prop_ex "$<TARGET_PROPERTY:PKG::${pkg},${prop}>")
-      string(APPEND exports "$<$<BOOL:${prop_ex}>:  ${prop} \"${prop_ex}\"\n>")
+      set(exports "${exports}$<$<BOOL:${prop_ex}>:  ${prop} \"${prop_ex}\"\n>")
 
     endforeach(prop)
 
@@ -412,9 +412,9 @@ function(export_packages filename)
       endif()
     endwhile(stack)
 
-    string(APPEND exports "  INTERFACE_LINK_LIBRARIES \"${libraries}\"\n")
+    set(exports "${exports}  INTERFACE_LINK_LIBRARIES \"${libraries}\"\n")
 
-    string(APPEND exports ")\n")
+    set(exports "${exports})\n")
   endforeach(pkg)
 
   file(GENERATE OUTPUT "${filename}" CONTENT "${exports}")
diff --git a/dtool/CompilerFlags.cmake b/dtool/CompilerFlags.cmake
index f22284b39b..5bda795d14 100644
--- a/dtool/CompilerFlags.cmake
+++ b/dtool/CompilerFlags.cmake
@@ -13,9 +13,9 @@ include(CheckCXXCompilerFlag)
 if(CMAKE_VERSION VERSION_LESS "3.1")
   check_cxx_compiler_flag("-std=gnu++11" COMPILER_SUPPORTS_CXX11)
   if(COMPILER_SUPPORTS_CXX11)
-    string(APPEND CMAKE_CXX_FLAGS " -std=gnu++11")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=gnu++11")
   else()
-    string(APPEND CMAKE_CXX_FLAGS " -std=gnu++0x")
+    set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=gnu++0x")
   endif()
 
 else()
@@ -79,26 +79,26 @@ endforeach(_type)
 
 # Set warning levels
 if(MSVC)
-  string(APPEND CMAKE_C_FLAGS " /W3")
-  string(APPEND CMAKE_CXX_FLAGS " /W3")
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} /W3")
+  set(CMAKE_CCXX_FLAGS "${CMAKE_CXX_FLAGS} /W3")
 
 else()
-  string(APPEND CMAKE_C_FLAGS " -Wall")
-  string(APPEND CMAKE_CXX_FLAGS " -Wall")
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall")
 
 endif()
 
 if(NOT "x${CMAKE_CXX_COMPILER_ID}" STREQUAL "xMSVC")
   set(disable_flags "-Wno-unused-function -Wno-unused-parameter")
-  string(APPEND CMAKE_C_FLAGS " ${disable_flags}")
-  string(APPEND CMAKE_CXX_FLAGS " ${disable_flags} -Wno-reorder")
-  string(APPEND CMAKE_CXX_FLAGS_RELEASE " -Wno-unused-variable")
-  string(APPEND CMAKE_CXX_FLAGS_RELWITHDEBINFO " -Wno-unused-variable")
-  string(APPEND CMAKE_CXX_FLAGS_MINSIZEREL " -Wno-unused-variable")
+  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${disable_flags}")
+  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${disable_flags} -Wno-reorder")
+  set(CMAKE_CXX_FLAGS_RELEASE "${CMAKE_CXX_FLAGS_RELEASE} -Wno-unused-variable")
+  set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "${CMAKE_CXX_FLAGS_RELWITHDEBINFO} -Wno-unused-variable")
+  set(CMAKE_CXX_FLAGS_MINSIZEREL "${CMAKE_CXX_FLAGS_MINSIZEREL} -Wno-unused-variable")
 
   if(MSVC)
-    # Clang behaving as MSVC
-    string(APPEND CMAKE_C_FLAGS " -Wno-unused-command-line-argument")
+    # Clang behaving as MSVC`
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-unused-command-line-argument")
     set(CMAKE_CXX_FLAGS
       "${CMAKE_CXX_FLAGS} -Wno-microsoft-template -Wno-unused-command-line-argument")
   endif()