diff --git a/test/tools/llvm-rc/include-paths.test b/test/tools/llvm-rc/include-paths.test
index 6acc967..0097ae8 100644
--- a/test/tools/llvm-rc/include-paths.test
+++ b/test/tools/llvm-rc/include-paths.test
@@ -13,6 +13,16 @@
 ; RUN: llvm-rc /FO %t.nested-include.res /I %p/Inputs/nested -- %p/Inputs/deep-include.rc
 ; RUN: llvm-readobj %t.nested-include.res | FileCheck --check-prefix=FOUND %s
 
+; The include dir can be specified via the INCLUDE env var too.
+; RUN: rm -f %t.nested-include.res
+; RUN: env INCLUDE=%p/Inputs/nested llvm-rc /FO %t.nested-include.res -- %p/Inputs/deep-include.rc
+; RUN: llvm-readobj %t.nested-include.res | FileCheck --check-prefix=FOUND %s
+
+; Specifying the /X option should make it ignore the INCLUDE variable.
+; RUN: rm -f %t.nested-include.res
+; RUN: not env INCLUDE=%p/Inputs/nested llvm-rc /X /FO %t.nested-include.res -- %p/Inputs/deep-include.rc 2>&1 \
+; RUN:   | FileCheck --check-prefix=MISSING %s
+
 ; Otherwise, it should not find the bitmap.
 ; RUN: rm -f %t.nested-include.res
 ; RUN: not llvm-rc /FO %t.nested-include.res -- %p/Inputs/deep-include.rc 2>&1 \
diff --git a/tools/llvm-rc/ResourceFileWriter.cpp b/tools/llvm-rc/ResourceFileWriter.cpp
index 2856fa8..0c92269 100644
--- a/tools/llvm-rc/ResourceFileWriter.cpp
+++ b/tools/llvm-rc/ResourceFileWriter.cpp
@@ -1553,10 +1553,11 @@
           Path, /*IsText=*/false, /*RequiresNullTerminator=*/false));
   }
 
-  if (auto Result =
-          llvm::sys::Process::FindInEnvPath("INCLUDE", File, Params.NoInclude))
-    return errorOrToExpected(MemoryBuffer::getFile(
-        *Result, /*IsText=*/false, /*RequiresNullTerminator=*/false));
+  if (!Params.NoInclude) {
+    if (auto Result = llvm::sys::Process::FindInEnvPath("INCLUDE", File))
+      return errorOrToExpected(MemoryBuffer::getFile(
+          *Result, /*IsText=*/false, /*RequiresNullTerminator=*/false));
+  }
 
   return make_error<StringError>("error : file not found : " + Twine(File),
                                  inconvertibleErrorCode());
diff --git a/tools/llvm-rc/ResourceFileWriter.h b/tools/llvm-rc/ResourceFileWriter.h
index d545a7a..0f3d593 100644
--- a/tools/llvm-rc/ResourceFileWriter.h
+++ b/tools/llvm-rc/ResourceFileWriter.h
@@ -35,7 +35,7 @@
 
 struct WriterParams {
   std::vector<std::string> Include;   // Additional folders to search for files.
-  std::vector<std::string> NoInclude; // Folders to exclude from file search.
+  bool NoInclude;                     // Ignore the INCLUDE variable.
   StringRef InputFilePath;            // The full path of the input file.
   int CodePage = CpAcp;               // The codepage for interpreting characters.
 };
diff --git a/tools/llvm-rc/llvm-rc.cpp b/tools/llvm-rc/llvm-rc.cpp
index e9027a2..2007ef9 100644
--- a/tools/llvm-rc/llvm-rc.cpp
+++ b/tools/llvm-rc/llvm-rc.cpp
@@ -142,7 +142,7 @@
   llvm::sys::fs::make_absolute(InputFile);
   Params.InputFilePath = InputFile;
   Params.Include = InputArgs.getAllArgValues(OPT_includepath);
-  Params.NoInclude = InputArgs.getAllArgValues(OPT_noinclude);
+  Params.NoInclude = InputArgs.hasArg(OPT_noinclude);
 
   if (InputArgs.hasArg(OPT_codepage)) {
     if (InputArgs.getLastArgValue(OPT_codepage)