Added Conflicting Global Accesses checker

This checker attempts to detect unsequenced accesses to global
variables. It recurses into function calls in the same translation unit,
and can handle fields on global structs/unions.

Author: ConcreteCactus

clang-tools-extra/clang-tidy/bugprone/BugproneTidyModule.cpp

@@ -19,6 +19,7 @@
 #include "CastingThroughVoidCheck.h"
 #include "ChainedComparisonCheck.h"
 #include "ComparePointerToMemberVirtualFunctionCheck.h"
+#include "ConflictingGlobalAccesses.h"
 #include "CopyConstructorInitCheck.h"
 #include "CrtpConstructorAccessibilityCheck.h"
 #include "DanglingHandleCheck.h"
@@ -124,6 +125,8 @@ class BugproneModule : public ClangTidyModule {
         "bugprone-chained-comparison");
     CheckFactories.registerCheck<ComparePointerToMemberVirtualFunctionCheck>(
         "bugprone-compare-pointer-to-member-virtual-function");
+    CheckFactories.registerCheck<ConflictingGlobalAccesses>(
+        "bugprone-conflicting-global-accesses");
     CheckFactories.registerCheck<CopyConstructorInitCheck>(
         "bugprone-copy-constructor-init");
     CheckFactories.registerCheck<DanglingHandleCheck>(

clang-tools-extra/clang-tidy/bugprone/CMakeLists.txt

@@ -15,6 +15,7 @@ add_clang_library(clangTidyBugproneModule STATIC
   CastingThroughVoidCheck.cpp
   ChainedComparisonCheck.cpp
   ComparePointerToMemberVirtualFunctionCheck.cpp
+  ConflictingGlobalAccesses.cpp
   CopyConstructorInitCheck.cpp
   CrtpConstructorAccessibilityCheck.cpp
   DanglingHandleCheck.cpp