diff --git a/cmake/modules/SetUpWindows.cmake b/cmake/modules/SetUpWindows.cmake
index 09879e526b2af..a2ddaa23f49cf 100644
--- a/cmake/modules/SetUpWindows.cmake
+++ b/cmake/modules/SetUpWindows.cmake
@@ -31,14 +31,17 @@ elseif(MSVC)
   math(EXPR VC_MINOR "${MSVC_VERSION} % 100")
 
   #---Select compiler flags----------------------------------------------------------------
+  if(winrtdebug AND dev)
+    set(ROOT_RTC_FLAGS "-RTC1")
+  endif()
   set(CMAKE_CXX_FLAGS_RELWITHDEBINFO "-MD -O2 -Ob2 -Z7 -DNDEBUG")
   set(CMAKE_CXX_FLAGS_MINSIZEREL     "-MD -O1 -Ob1 -DNDEBUG")
   set(CMAKE_CXX_FLAGS_RELEASE        "-MD -O2 -Ob2 -DNDEBUG")
-  set(CMAKE_CXX_FLAGS_DEBUG          "-MDd -Od -Ob0 -Z7")
+  set(CMAKE_CXX_FLAGS_DEBUG          "-MDd -Od -Ob0 -Z7 ${ROOT_RTC_FLAGS}")
   set(CMAKE_C_FLAGS_RELWITHDEBINFO   "-MD -O2 -Ob2 -Z7 -DNDEBUG")
   set(CMAKE_C_FLAGS_MINSIZEREL       "-MD -O1 -Ob1 -DNDEBUG")
   set(CMAKE_C_FLAGS_RELEASE          "-MD -O2 -Ob2 -DNDEBUG")
-  set(CMAKE_C_FLAGS_DEBUG            "-MDd -Od -Ob0 -Z7")
+  set(CMAKE_C_FLAGS_DEBUG            "-MDd -Od -Ob0 -Z7 ${ROOT_RTC_FLAGS}")
 
   if(winrtdebug)
     if (CMAKE_SIZEOF_VOID_P EQUAL 8)
diff --git a/cmake/scripts/compiledata.win32.in b/cmake/scripts/compiledata.win32.in
index cff8d4d3558f5..2f64008f983ed 100644
--- a/cmake/scripts/compiledata.win32.in
+++ b/cmake/scripts/compiledata.win32.in
@@ -7,8 +7,8 @@
 #define COMPILERVERSSTR "@CMAKE_CXX_COMPILER_ID@ @CMAKE_CXX_COMPILER_VERSION@"
 #define MAKESHAREDLIB "cl $Opt -nologo -TP -c @CMAKE_CXX_FLAGS@ @BLDCXXFLAGS@ $IncludePath $SourceFiles -Fo$ObjectFiles && bindexplib $LibName $ObjectFiles > $BuildDir\\$LibName.def && lib -nologo -MACHINE:@MACHINE_ARCH@ -out:$BuildDir\\$LibName.lib $ObjectFiles -def:$BuildDir\\$LibName.def && link -nologo $ObjectFiles -DLL -out:$BuildDir\\$LibName.dll $BuildDir\\$LibName.exp -LIBPATH:%ROOTSYS%\\lib  $LinkedLibs libCore.lib kernel32.lib advapi32.lib user32.lib gdi32.lib comdlg32.lib winspool.lib && if EXIST \"$BuildDir\\$LibName.dll.manifest\" ( mt -nologo -manifest \"$BuildDir\\$LibName.dll.manifest\" \"-outputresource:$BuildDir\\$LibName.dll;2\" && del \"$BuildDir\\$LibName.dll.manifest\" )"
 #define MAKEEXE "cl -nologo -TP -Iinclude -I..\\include -c $Opt @CMAKE_CXX_FLAGS@ @BLDCXXFLAGS@ $IncludePath $SourceFiles && link -opt:ref @CMAKE_EXE_FLAGS@ $ObjectFiles $LinkedLibs advapi32.lib -out:$ExeName  && if EXIST \"$ExeName.exe.manifest\" ( mt -nologo -manifest \"$ExeName.exe.manifest\" \"-outputresource:$ExeName.exe;1\" && del \"$ExeName.exe.manifest\" )"
-#define CXXOPT "@CMAKE_CXX_FLAGS_RELEASE@"
-#define CXXDEBUG "@CMAKE_CXX_FLAGS_DEBUG@"
+#define CXXOPT "@CMAKE_CXX_FLAGS_RELEASE@ @BLDCXXFLAGS@"
+#define CXXDEBUG "@CMAKE_CXX_FLAGS_DEBUG@ @BLDCXXFLAGS@"
 #define ROOTBUILD "release"
 #define LINKEDLIBS "-LIBPATH:%ROOTSYS%\\lib libCore.lib "
 #define INCLUDEPATH "-I%ROOTSYS%\\include"
diff --git a/core/base/src/TSystem.cxx b/core/base/src/TSystem.cxx
index a02fba94e1c5b..7b169455ccab3 100644
--- a/core/base/src/TSystem.cxx
+++ b/core/base/src/TSystem.cxx
@@ -2885,6 +2885,12 @@ int TSystem::CompileMacro(const char *filename, Option_t *opt,
          mode = kDebug;
       }
    }
+#if defined(_MSC_VER) && defined(_DEBUG)
+   // if ROOT is build in debug mode, ACLiC must also build in debug mode
+   // for compatibility reasons
+   if (!(mode & kDebug))
+      mode |= kDebug;
+#endif
    UInt_t verboseLevel = verbose ? 7 : gDebug;
    Bool_t flatBuildDir = (fAclicProperties & kFlatBuildDir) || (opt && strchr(opt,'-')!=nullptr);
 
@@ -3729,12 +3735,18 @@ int TSystem::CompileMacro(const char *filename, Option_t *opt,
    TString optdebFlags;
    if (mode & kDebug)
       optdebFlags = fFlagsDebug + " ";
+#ifdef WIN32
+   else
+#endif
    if (mode & kOpt)
       optdebFlags += fFlagsOpt;
    cmd.ReplaceAll("$Opt", optdebFlags);
 #ifdef WIN32
    R__FixLink(cmd);
    cmd.ReplaceAll("-std=", "-std:");
+   if (mode & kDebug) {
+      cmd.ReplaceAll(" && link ", "&& link /DEBUG ");
+   }
 #endif
 
    TString testcmd = fMakeExe;
diff --git a/core/dictgen/src/rootcling_impl.cxx b/core/dictgen/src/rootcling_impl.cxx
index e6e56da005292..32faf06421946 100644
--- a/core/dictgen/src/rootcling_impl.cxx
+++ b/core/dictgen/src/rootcling_impl.cxx
@@ -2135,6 +2135,10 @@ void AddPlatformDefines(std::vector<std::string> &clingArgs)
    clingArgs.push_back(platformDefines);
    snprintf(platformDefines, 64, "-DG__VISUAL=%ld", (long)_MSC_VER);
    clingArgs.push_back(platformDefines);
+#if defined(_WIN64) && defined(_DEBUG)
+   snprintf(platformDefines, 64, "-D_ITERATOR_DEBUG_LEVEL=0");
+   clingArgs.push_back(platformDefines);
+#endif
 #endif
 }
 
diff --git a/graf2d/win32gdk/gdk/src/glib/gmessages.c b/graf2d/win32gdk/gdk/src/glib/gmessages.c
index ac1fef072dc15..c915f4e8fbd13 100644
--- a/graf2d/win32gdk/gdk/src/glib/gmessages.c
+++ b/graf2d/win32gdk/gdk/src/glib/gmessages.c
@@ -544,7 +544,8 @@ g_logv (const gchar   *log_domain,
 #endif
 # if defined (_MSC_VER) && defined (_DEBUG)
 	      /* let's see the call stack ... */
-	      __asm int 3
+	      /* __asm int 3 */
+	      __debugbreak();
 # endif
 	      abort ();
 #endif /* !G_ENABLE_DEBUG || !SIGTRAP */
diff --git a/interpreter/CMakeLists.txt b/interpreter/CMakeLists.txt
index 7131b1453dcf8..dbcdf669b9d3f 100644
--- a/interpreter/CMakeLists.txt
+++ b/interpreter/CMakeLists.txt
@@ -176,8 +176,12 @@ if(builtin_llvm)
     if(CMAKE_BUILD_TYPE MATCHES "Debug"
      OR LLVM_BUILD_TYPE MATCHES "(Debug|RelWithDebInfo)")
       set(LLVM_ENABLE_ASSERTIONS TRUE)
+      if(NOT DEFINED LLVM_ENABLE_DUMP)
+        set(LLVM_ENABLE_DUMP TRUE)
+      endif()
     else()
       set(LLVM_ENABLE_ASSERTIONS FALSE)
+      set(LLVM_ENABLE_DUMP FALSE)
     endif()
   endif()
 
diff --git a/interpreter/cling/lib/Interpreter/CIFactory.cpp b/interpreter/cling/lib/Interpreter/CIFactory.cpp
index 3d7fcf58231bf..594df5b62243e 100644
--- a/interpreter/cling/lib/Interpreter/CIFactory.cpp
+++ b/interpreter/cling/lib/Interpreter/CIFactory.cpp
@@ -849,6 +849,9 @@ namespace {
     PPOpts.addMacroDef("__CLING__GNUC_MINOR__=" ClingStringify(__GNUC_MINOR__));
 #elif defined(_MSC_VER)
     PPOpts.addMacroDef("__CLING__MSVC__=" ClingStringify(_MSC_VER));
+#if defined(_WIN64) && defined(_DEBUG)
+    PPOpts.addMacroDef("_ITERATOR_DEBUG_LEVEL=0");
+#endif
 #endif
 
 // https://gcc.gnu.org/onlinedocs/libstdc++/manual/using_dual_abi.html
diff --git a/io/io/src/TFile.cxx b/io/io/src/TFile.cxx
index 4565fa1f45019..a4162bffbe56c 100644
--- a/io/io/src/TFile.cxx
+++ b/io/io/src/TFile.cxx
@@ -3222,6 +3222,11 @@ void TFile::MakeProject(const char *dirname, const char * /*classes*/,
    } else {
       sOpt = gSystem->GetFlagsDebug();
    }
+#if defined(_MSC_VER) && defined(_DEBUG)
+   // if ROOT is build in debug mode, ACLiC must also build in debug mode
+   // for compatibility reasons
+   sOpt = gSystem->GetFlagsDebug();
+#endif
    cmd.ReplaceAll("$Opt", sOpt);
 
    if (genreflex) {