diff --git a/.clang-format b/.clang-format
index 020d4667..c3bb0335 100644
--- a/.clang-format
+++ b/.clang-format
@@ -80,6 +80,7 @@ IncludeCategories:
 IncludeIsMainRegex: '(Test)?$'
 IncludeIsMainSourceRegex: ''
 IndentCaseLabels: false
+IndentExternBlock: NoIndent
 IndentGotoLabels: true
 IndentPPDirectives: None
 IndentWidth:     2
diff --git a/.github/workflows/cpplint.yml b/.github/workflows/cpplint.yml
index 980e0080..72da335e 100644
--- a/.github/workflows/cpplint.yml
+++ b/.github/workflows/cpplint.yml
@@ -20,7 +20,7 @@ jobs:
       uses: actions/checkout@v3
 
     - name: Install ClangFormat
-      run: sudo apt-get install -y clang-format
+      run: sudo apt-get install -y clang-format-12
 
     - name: Run cpplint
       run: make cpplint
diff --git a/Makefile b/Makefile
index 2831d0e4..d1a1a1f8 100644
--- a/Makefile
+++ b/Makefile
@@ -147,14 +147,14 @@ lib: $(LIBOBJTARGETS) $(INCTARGETS) $(LIBTARGET)
 tests: $(TESTSBINS)
 
 cpplint:
-	clang-format -style=file --verbose --Werror --dry-run $(CPPSOURCES)
+	clang-format-12 -style=file --verbose --Werror --dry-run $(CPPSOURCES)
 
 cpplint-autofix:
-	clang-format -style=file --verbose --Werror -i $(CPPSOURCES)
+	clang-format-12 -style=file --verbose --Werror -i $(CPPSOURCES)
 
 # Run cpplint on a single file, example: make cpplint-file INPUTFILE=src/bootstrap/bootstrap.cc
 cpplint-file-autofix:
-	clang-format -style=file --verbose --Werror -i $(INPUTFILE)
+	clang-format-12 -style=file --verbose --Werror -i $(INPUTFILE)
 
 # Compile libobjs
 $(BUILDDIR)/$(OBJDIR)/%.o: %.cc $(HEADERS)