diff --git a/.arclint b/.arclint
--- a/.arclint
+++ b/.arclint
@@ -2,7 +2,7 @@
   "linters": {
     "clang-format": {
       "type": "script-and-regex",
-      "script-and-regex.script": "bash utils/arcanist/clang-format.sh",
+      "script-and-regex.script": "cmd utils\\arcanist\\clang-format.sh",
       "script-and-regex.regex": "/^(?P<severity>[[:alpha:]]+)\n(?P<message>[^\n]+)\n(====|(?P<line>\\d),(?P<char>\\d)\n(?P<original>.*)>>>>\n(?P<replacement>.*)<<<<\n)$/s",
       "include": [
         "(\\.(cc|cpp|h)$)"
diff --git a/clang/include/clang/Format/Format.h b/clang/include/clang/Format/Format.h
--- a/clang/include/clang/Format/Format.h
+++ b/clang/include/clang/Format/Format.h
@@ -2645,7 +2645,9 @@
   enum LanguageKind : unsigned char {
     /// Do not use.
     LK_None,
-    /// Should be used for C, C++.
+    /// Should be used for C.
+    LK_C,
+    /// Should be used for C++.
     LK_Cpp,
     /// Should be used for C#.
     LK_CSharp,
@@ -2666,6 +2668,8 @@
     /// (https://developers.google.com/protocol-buffers/).
     LK_TextProto
   };
+
+  bool isC() const { return Language == LK_C; }
   bool isCpp() const { return Language == LK_Cpp || Language == LK_ObjC; }
   bool isCSharp() const { return Language == LK_CSharp; }
   bool isJson() const { return Language == LK_Json; }
@@ -4183,6 +4187,8 @@
 // Returns a string representation of ``Language``.
 inline StringRef getLanguageName(FormatStyle::LanguageKind Language) {
   switch (Language) {
+  case FormatStyle::LK_C:
+    return "C";
   case FormatStyle::LK_Cpp:
     return "C++";
   case FormatStyle::LK_CSharp:
diff --git a/clang/lib/Format/BreakableToken.cpp b/clang/lib/Format/BreakableToken.cpp
--- a/clang/lib/Format/BreakableToken.cpp
+++ b/clang/lib/Format/BreakableToken.cpp
@@ -110,7 +110,7 @@
     // -Wcomment.
     // Avoid introducing multiline comments by not allowing a break right
     // after '\'.
-    if (Style.isCpp()) {
+    if (Style.isCpp() || Style.isC()) {
       StringRef::size_type LastNonBlank =
           Text.find_last_not_of(Blanks, SpaceOffset);
       if (LastNonBlank != StringRef::npos && Text[LastNonBlank] == '\\') {
diff --git a/clang/lib/Format/ContinuationIndenter.cpp b/clang/lib/Format/ContinuationIndenter.cpp
--- a/clang/lib/Format/ContinuationIndenter.cpp
+++ b/clang/lib/Format/ContinuationIndenter.cpp
@@ -356,7 +356,7 @@
     return false;
   if ((startsNextParameter(Current, Style) || Previous.is(tok::semi) ||
        (Previous.is(TT_TemplateCloser) && Current.is(TT_StartOfName) &&
-        Style.isCpp() &&
+        (Style.isCpp() || Style.isC()) &&
         // FIXME: This is a temporary workaround for the case where clang-format
         // sets BreakBeforeParameter to avoid bin packing and this creates a
         // completely unnecessary line break after a template type that isn't
@@ -917,7 +917,8 @@
   // Any break on this level means that the parent level has been broken
   // and we need to avoid bin packing there.
   bool NestedBlockSpecialCase =
-      (!Style.isCpp() && Current.is(tok::r_brace) && State.Stack.size() > 1 &&
+      (!Style.isCpp() && !Style.isC() && Current.is(tok::r_brace) &&
+       State.Stack.size() > 1 &&
        State.Stack[State.Stack.size() - 2].NestedBlockInlined) ||
       (Style.Language == FormatStyle::LK_ObjC && Current.is(tok::r_brace) &&
        State.Stack.size() > 1 && !Style.ObjCBreakBeforeNestedBlockParam);
diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -57,6 +57,7 @@
 namespace yaml {
 template <> struct ScalarEnumerationTraits<FormatStyle::LanguageKind> {
   static void enumeration(IO &IO, FormatStyle::LanguageKind &Value) {
+    IO.enumCase(Value, "C", FormatStyle::LK_C);
     IO.enumCase(Value, "Cpp", FormatStyle::LK_Cpp);
     IO.enumCase(Value, "Java", FormatStyle::LK_Java);
     IO.enumCase(Value, "JavaScript", FormatStyle::LK_JavaScript);
@@ -2914,7 +2915,7 @@
 tooling::Replacements
 fixCppIncludeInsertions(StringRef Code, const tooling::Replacements &Replaces,
                         const FormatStyle &Style) {
-  if (!Style.isCpp())
+  if (!Style.isCpp() && !Style.isC())
     return Replaces;
 
   tooling::Replacements HeaderInsertions;
@@ -3040,7 +3041,8 @@
       AnalyzerPass;
   SmallVector<AnalyzerPass, 4> Passes;
 
-  if (Style.isCpp() && Style.QualifierAlignment != FormatStyle::QAS_Leave) {
+  if ((Style.isCpp() || Style.isC()) &&
+      Style.QualifierAlignment != FormatStyle::QAS_Leave) {
     Passes.emplace_back([&](const Environment &Env) {
       return QualifierAlignmentFixer(Env, Expanded, Code, Ranges,
                                      FirstStartColumn, NextStartColumn,
@@ -3126,7 +3128,8 @@
                               ArrayRef<tooling::Range> Ranges,
                               StringRef FileName) {
   // cleanups only apply to C++ (they mostly concern ctor commas etc.)
-  if (Style.Language != FormatStyle::LK_Cpp)
+  if (Style.Language != FormatStyle::LK_Cpp &&
+      Style.Language != FormatStyle::LK_C)
     return tooling::Replacements();
   auto Env = Environment::make(Code, FileName, Ranges);
   if (!Env)
@@ -3190,7 +3193,7 @@
   LangOpts.Char8 = LexingStd >= FormatStyle::LS_Cpp20;
 
   LangOpts.LineComment = 1;
-  bool AlternativeOperators = Style.isCpp();
+  bool AlternativeOperators = Style.isCpp() || Style.isC();
   LangOpts.CXXOperatorNames = AlternativeOperators ? 1 : 0;
   LangOpts.Bool = 1;
   LangOpts.ObjC = 1;
diff --git a/clang/lib/Format/FormatTokenLexer.cpp b/clang/lib/Format/FormatTokenLexer.cpp
--- a/clang/lib/Format/FormatTokenLexer.cpp
+++ b/clang/lib/Format/FormatTokenLexer.cpp
@@ -104,7 +104,7 @@
     return;
   if (tryMergeForEach())
     return;
-  if (Style.isCpp() && tryTransformTryUsageForC())
+  if ((Style.isCpp() || Style.isC()) && tryTransformTryUsageForC())
     return;
 
   if (Style.isJavaScript() || Style.isCSharp()) {
@@ -1023,7 +1023,7 @@
     Column = FormatTok->LastLineColumnWidth;
   }
 
-  if (Style.isCpp()) {
+  if (Style.isCpp() || Style.isC()) {
     auto it = Macros.find(FormatTok->Tok.getIdentifierInfo());
     if (!(Tokens.size() > 0 && Tokens.back()->Tok.getIdentifierInfo() &&
           Tokens.back()->Tok.getIdentifierInfo()->getPPKeywordID() ==
diff --git a/clang/lib/Format/TokenAnnotator.cpp b/clang/lib/Format/TokenAnnotator.cpp
--- a/clang/lib/Format/TokenAnnotator.cpp
+++ b/clang/lib/Format/TokenAnnotator.cpp
@@ -799,7 +799,8 @@
           if (Previous->is(TT_JsTypeOptionalQuestion))
             Previous = Previous->getPreviousNonComment();
           if ((CurrentToken->is(tok::colon) &&
-               (!Contexts.back().ColonIsDictLiteral || !Style.isCpp())) ||
+               (!Contexts.back().ColonIsDictLiteral ||
+                (!Style.isCpp() && !Style.isC()))) ||
               Style.Language == FormatStyle::LK_Proto ||
               Style.Language == FormatStyle::LK_TextProto) {
             Left->setType(TT_DictLiteral);
@@ -1873,7 +1874,7 @@
   /// Determine whether ')' is ending a cast.
   bool rParenEndsCast(const FormatToken &Tok) {
     // C-style casts are only used in C++, C# and Java.
-    if (!Style.isCSharp() && !Style.isCpp() &&
+    if (!Style.isCSharp() && !Style.isCpp() && !Style.isC() &&
         Style.Language != FormatStyle::LK_Java)
       return false;
 
@@ -2566,7 +2567,8 @@
     calculateArrayInitializerColumnList(Line);
 
   while (Current) {
-    if (isFunctionDeclarationName(Style.isCpp(), *Current, Line))
+    if (isFunctionDeclarationName((Style.isCpp() || Style.isC()), *Current,
+                                  Line))
       Current->setType(TT_FunctionDeclarationName);
     const FormatToken *Prev = Current->Previous;
     if (Current->is(TT_LineComment)) {
@@ -3233,7 +3235,8 @@
       if (Left.isOneOf(tok::kw_try, Keywords.kw___except, tok::kw_catch))
         return Style.SpaceBeforeParensOptions.AfterControlStatements ||
                spaceRequiredBeforeParens(Right);
-      if (Left.isOneOf(tok::kw_new, tok::kw_delete))
+      if (Style.Language != FormatStyle::LK_C &&
+          Left.isOneOf(tok::kw_new, tok::kw_delete))
         return Style.SpaceBeforeParens != FormatStyle::SBPO_Never ||
                spaceRequiredBeforeParens(Right);
     }
@@ -3813,7 +3816,8 @@
     if (Right.is(tok::plus) && Left.is(tok::string_literal) && Right.Next &&
         Right.Next->is(tok::string_literal))
       return true;
-  } else if (Style.Language == FormatStyle::LK_Cpp ||
+  } else if (Style.Language == FormatStyle::LK_C ||
+             Style.Language == FormatStyle::LK_Cpp ||
              Style.Language == FormatStyle::LK_ObjC ||
              Style.Language == FormatStyle::LK_Proto ||
              Style.Language == FormatStyle::LK_TableGen ||
diff --git a/clang/lib/Format/UnwrappedLineFormatter.cpp b/clang/lib/Format/UnwrappedLineFormatter.cpp
--- a/clang/lib/Format/UnwrappedLineFormatter.cpp
+++ b/clang/lib/Format/UnwrappedLineFormatter.cpp
@@ -97,7 +97,8 @@
   /// For example, 'public:' labels in classes are offset by 1 or 2
   /// characters to the left from their level.
   int getIndentOffset(const FormatToken &RootToken) {
-    if (Style.Language == FormatStyle::LK_Java || Style.isJavaScript() ||
+    if (Style.Language == FormatStyle::LK_C ||
+        Style.Language == FormatStyle::LK_Java || Style.isJavaScript() ||
         Style.isCSharp())
       return 0;
     if (RootToken.isAccessSpecifier(false) ||
diff --git a/clang/lib/Format/UnwrappedLineParser.cpp b/clang/lib/Format/UnwrappedLineParser.cpp
--- a/clang/lib/Format/UnwrappedLineParser.cpp
+++ b/clang/lib/Format/UnwrappedLineParser.cpp
@@ -1218,7 +1218,8 @@
   case tok::kw_public:
   case tok::kw_protected:
   case tok::kw_private:
-    if (Style.Language == FormatStyle::LK_Java || Style.isJavaScript() ||
+    if (Style.Language == FormatStyle::LK_C ||
+        Style.Language == FormatStyle::LK_Java || Style.isJavaScript() ||
         Style.isCSharp())
       nextToken();
     else
@@ -1450,7 +1451,7 @@
       if (!parseEnum())
         break;
       // This only applies for C++.
-      if (!Style.isCpp()) {
+      if (!Style.isCpp() && !Style.isC()) {
         addUnwrappedLine();
         return;
       }
@@ -1493,7 +1494,8 @@
       parseParens();
       // Break the unwrapped line if a K&R C function definition has a parameter
       // declaration.
-      if (!IsTopLevel || !Style.isCpp() || !Previous || FormatTok->is(tok::eof))
+      if (!IsTopLevel || (!Style.isCpp() && !Style.isC()) || !Previous ||
+          FormatTok->is(tok::eof))
         break;
       if (isC78ParameterDecl(FormatTok, Tokens->peekNextToken(), Previous)) {
         addUnwrappedLine();
@@ -1601,7 +1603,7 @@
         break;
       }
 
-      if (Style.isCpp() && FormatTok->is(TT_StatementMacro)) {
+      if ((Style.isCpp() || Style.isC()) && FormatTok->is(TT_StatementMacro)) {
         parseStatementMacro();
         return;
       }
@@ -2647,7 +2649,7 @@
       nextToken();
       // If there are two identifiers in a row, this is likely an elaborate
       // return type. In Java, this can be "implements", etc.
-      if (Style.isCpp() && FormatTok->is(tok::identifier))
+      if ((Style.isCpp() || Style.isC()) && FormatTok->is(tok::identifier))
         return false;
     }
   }
diff --git a/clang/tools/clang-format/ClangFormat.cpp b/clang/tools/clang-format/ClangFormat.cpp
--- a/clang/tools/clang-format/ClangFormat.cpp
+++ b/clang/tools/clang-format/ClangFormat.cpp
@@ -121,6 +121,12 @@
     Verbose("verbose", cl::desc("If set, shows the list of processed files"),
             cl::cat(ClangFormatCategory));
 
+static cl::opt<std::string>
+    SetLanguage("set-language",
+                cl::desc("Manually sets the programming language clang-format "
+                         "interprets files as"),
+                cl::init(""), cl::cat(ClangFormatCategory));
+
 // Use --dry-run to match other LLVM tools when you mean do it but don't
 // actually do it
 static cl::opt<bool>
@@ -458,6 +464,12 @@
   Replacements Replaces = sortIncludes(*FormatStyle, Code->getBuffer(), Ranges,
                                        AssumedFileName, &CursorPosition);
 
+  if (SetLanguage.getNumOccurrences() != 0) {
+
+    if (SetLanguage.getValue() == "C" || SetLanguage.getValue() == "c") {
+      FormatStyle->Language = FormatStyle::LK_C;
+    }
+  }
   // To format JSON insert a variable to trick the code into thinking its
   // JavaScript.
   if (FormatStyle->isJson() && !FormatStyle->DisableFormat) {