diff --git a/scripts/clang_format_all.sh b/scripts/clang_format_all.sh
new file mode 100644
index 000000000..58f26af55
--- /dev/null
+++ b/scripts/clang_format_all.sh
@@ -0,0 +1,62 @@
+#!/bin/sh
+
+CLANG_MAJOR=3
+CLANG_MINOR=8
+
+CLANG_FORMAT_VERSION=$CLANG_MAJOR.$CLANG_MINOR
+
+# Locate the clang-format executable. We try:
+#   - the existing value of $CLANG_FORMAT
+#   - the first command line argument to the script
+#   - in order:
+#      clang-format-Maj.Min
+#      clang-format-Maj
+#      clang-format
+
+# define a function to check the current $CLANG_FORMAT
+valid_clang_format() {
+	if which $CLANG_FORMAT > /dev/null 2>&1; then
+		if $CLANG_FORMAT --version | grep -q $CLANG_FORMAT_VERSION; then
+			echo "Located $CLANG_FORMAT";
+			return 0;
+		fi
+	fi
+
+	return 1;
+}
+
+if ! valid_clang_format; then
+	# if not valid yet, first try the command line parameter
+	CLANG_FORMAT=$1
+fi;
+
+if ! valid_clang_format; then
+	# Next try the full version
+	CLANG_FORMAT=clang-format-$CLANG_MAJOR.$CLANG_MINOR
+fi;
+
+if ! valid_clang_format; then
+	# Then -maj just in case
+	CLANG_FORMAT=clang-format-$CLANG_MAJOR
+fi;
+
+if ! valid_clang_format; then
+	# Then finally with no version suffix
+	CLANG_FORMAT=clang-format
+fi;
+
+# Check if we have a valid $CLANG_FORMAT
+if ! valid_clang_format; then
+	# If we didn't find one, bail out
+	echo "Couldn't find correct clang-format version, was looking for $CLANG_FORMAT_VERSION"
+	echo "Renderdoc requires a very specific clang-format version to ensure there isn't any"
+	echo "variance between versions that can happen. You can install it as"
+	echo "'clang-format-$CLANG_FORMAT_VERSION' so that it doesn't interfere with any other"
+	echo "versions you might have installed, and this script will find it there"
+	exit 1;
+fi;
+
+# Search through the code that should be formatted, exclude any non-renderdoc code.
+FILES=$(find qrenderdoc/ renderdoc/ renderdoccmd/ renderdocshim/ -type f -regex '.*\(/3rdparty/\|/official/\|resource.h\).*' -prune -o -regex '.*\.\(c\|cpp\|h\)$' -print)
+
+$CLANG_FORMAT -i -style=file $FILES
diff --git a/scripts/travis/linux_setup.sh b/scripts/travis/linux_setup.sh
index d5c46f93c..cd421e586 100644
--- a/scripts/travis/linux_setup.sh
+++ b/scripts/travis/linux_setup.sh
@@ -8,17 +8,36 @@ wget -O - http://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
 sudo apt-get update -qq 
 sudo apt-get install --allow-unauthenticated -y -qq libx11-dev mesa-common-dev libgl1-mesa-dev qt56base qt56svg qt56x11extras libxcb-keysyms1-dev gdb clang-format-3.8 g++-6
 
+# check last 100 commits are all correctly sized. First line must be no
+# longer than 72 characters, so it fits in git log and github history
+if git log --oneline | head -n 100 | cut -d ' ' -f2- | grep -q '.\{73\}'; then
+  echo "***************************************************";
+  echo "*** Some of your commit messages summaries are  ***";
+  echo "*** longer than 72 characters.                  ***";
+  echo "*** Please shorten them so they fit <= 72 chars ***";
+  echo "*** on the first line, with a longer summary in ***";
+  echo "*** the body after a blank line.                ***";
+  echo "*** For more information see CONTRIBUTING.md.   ***";
+  echo "*** Thanks!                                     ***";
+  echo "***                                             ***";
+  echo "*** Commit messages:                            ***";
+  echo;
+  git log --oneline | head -n 100 | cut -d ' ' -f2- | grep '.\{73\}'
+  echo;
+  echo "***************************************************";
+  exit 1;
+fi
+
 # check formatting matches clang-format-3.8. Since newer versions can have
 # changes in formatting even without any rule changes, we have to fix on a
 # single version.
-
-clang-format-3.8 -i -style=file $(find qrenderdoc/ renderdoc/ renderdoccmd/ renderdocshim/ -type f -regex '.*\(/3rdparty/\|/official/\|resource.h\).*' -prune -o -regex '.*\.\(c\|cpp\|h\)$' -print)
+. ./scripts/clang_format_all.sh
 
 git clean -f
 
-# this swallows the exit code so we won't fail until we print the diff in
-# the next line, but allows us to print a friendlier message to anyone
-# looking at the build log
+# Print any diff here, so the error message below is the last thing
+git diff
+
 git diff --quiet || (
   echo "***************************************************";
   echo "*** The code is not clean against clang-format  ***";
@@ -27,6 +46,5 @@ git diff --quiet || (
   echo "*** the relevant commits. Do not add a commit   ***";
   echo "*** for just formatting fixes. Thanks!          ***";
   echo "***************************************************";
+  exit 1;
   )
-
-git diff --exit-code