From 571f770dc0363dcd4d0d3503c2cafab465f445b5 Mon Sep 17 00:00:00 2001
From: Joey Vagedes <joey.vagedes@gmail.com>
Date: Mon, 12 Jun 2023 14:34:54 -0700
Subject: [PATCH 1/2] BaseTools: Detect invalid library override

Ensures LIBRARY_CLASS as specified in the library override INF defines
section is the same value as the library class specified in the
override line.
---
 .../Python/Workspace/WorkspaceCommon.py       | 20 +++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/BaseTools/Source/Python/Workspace/WorkspaceCommon.py b/BaseTools/Source/Python/Workspace/WorkspaceCommon.py
index 9e506fc646..bfd520d534 100644
--- a/BaseTools/Source/Python/Workspace/WorkspaceCommon.py
+++ b/BaseTools/Source/Python/Workspace/WorkspaceCommon.py
@@ -110,6 +110,26 @@ def GetModuleLibInstances(Module, Platform, BuildDatabase, Arch, Target, Toolcha
         if LibraryClass.startswith("NULL"):
             Module.LibraryClasses[LibraryClass] = Platform.Modules[str(Module)].LibraryClasses[LibraryClass]
 
+        # MU_CHANGE begin
+
+        # Compares the Library class being over written (var: LibraryClass) to the actual library class that is
+        # is doing the overridding.
+        # 
+        # i.e. ExampleLib|Path/To/ExampleLibBase.inf:
+        #     ensuring ExampleLib == LIBRARY_CLASS in the define section of ExampleLibBase.inf
+        else:
+            path = Platform.Modules[str(Module)].LibraryClasses[LibraryClass]
+            match = False
+            for LibraryClassObj in BuildDatabase[path, Arch, Target, Toolchain].LibraryClass:
+                if LibraryClass == LibraryClassObj.LibraryClass:
+                    match = True
+            
+            if not match:
+                EdkLogger.error("build", BUILD_ERROR,
+                              "Library override [%s] library class does not match specified library class: [%s]" % (path, LibraryClass),
+                              File=FileName)
+        # MU_CHANGE end
+
     # EdkII module
     LibraryConsumerList = [Module]
     Constructor = []

From 4322c3db0f60622b98e98a7599f44b49b029f1c6 Mon Sep 17 00:00:00 2001
From: Joey Vagedes <joey.vagedes@gmail.com>
Date: Mon, 12 Jun 2023 14:48:29 -0700
Subject: [PATCH 2/2] update

---
 BaseTools/Source/Python/Workspace/WorkspaceCommon.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/BaseTools/Source/Python/Workspace/WorkspaceCommon.py b/BaseTools/Source/Python/Workspace/WorkspaceCommon.py
index bfd520d534..1ddc8d530f 100644
--- a/BaseTools/Source/Python/Workspace/WorkspaceCommon.py
+++ b/BaseTools/Source/Python/Workspace/WorkspaceCommon.py
@@ -126,7 +126,7 @@ def GetModuleLibInstances(Module, Platform, BuildDatabase, Arch, Target, Toolcha
             
             if not match:
                 EdkLogger.error("build", BUILD_ERROR,
-                              "Library override [%s] library class does not match specified library class: [%s]" % (path, LibraryClass),
+                              "LIBRARY_CLASS for override: [%s] does not match the library class being overridden: [%s]" % (path, LibraryClass),
                               File=FileName)
         # MU_CHANGE end