Add variable for clang-tidy name when building on Linux

Travis has the correct clang-tidy version of 7, while CircleCI needs
clang-tidy-7.

.circleci/config.yml

@@ -97,6 +97,7 @@ jobs:
             QMAKE_SPEC: linux-clang
             QT_SELECT: opt-qt512
             USE_TIDY: TRUE
+            CLANG_TIDY_EXECUTABLE: clang-tidy-7
             MAKE_JOBS: 2
         docker:
             - image: "ubuntu:xenial"

build_scripts/linux/run-clang-tidy.sh

@@ -1,10 +1,15 @@
 set +e
-clang-tidy-7 --version
+
+if [[ -z $CLANG_TIDY_EXECUTABLE ]]; then
+    CLANG_TIDY_EXECUTABLE='clang-tidy'
+fi
+
+$CLANG_TIDY_EXECUTABLE --version
 
 ERROR=0
 for file in $(find ../src -name "*.cpp"); do
     echo $file
-    clang-tidy-7 $file
+    $CLANG_TIDY_EXECUTABLE $file
 
     EXIT=$?
     if [[ $EXIT != 0 ]]; then

docs/building_for_linux.md

@@ -166,6 +166,8 @@ The following environmental variables are relevant for building the project.
 | `NO_X11`              | If set the application will be compiled without X11 specific libraries. This disables certain things like sending keystrokes from VR.  |
 | `NO_DBUS`              | If set the application will be compiled without DBUS specific functionality. This disables certain things like media keys.  |
 | `MAKE_JOBS`              | Argument to `make --jobs`. Defaults to nothing (unlimited amount of jobs).  |
+| `CLANG_TIDY_EXECUTABLE`              | Name of the `clang-tidy` executable. Defaults to `clang-tidy`. Used for specifying a specific version or path, for example `clang-tidy-7`.  |
+
 
 # Building