Fixing clang compilation and supporting clang-tidy

- clang.c includes necessary functions to make clang compiler work (tested on teensy 3.1)
- Added support code to generate a compile_commands.json for clang-tidy
  * Updates the symlink whenever cmake or make is called (Unix OSs only)

.clang-tidy

@@ -0,0 +1,16 @@
+---
+Checks:          'clang-diagnostic-*,clang-analyzer-*,-clang-analyzer-alpha*'
+HeaderFilterRegex: ''
+AnalyzeTemporaryDtors: false
+User:            hyatt
+CheckOptions:    
+  - key:             google-readability-braces-around-statements.ShortStatementLines
+    value:           '1'
+  - key:             google-readability-function-size.StatementThreshold
+    value:           '800'
+  - key:             google-readability-namespace-comments.ShortNamespaceLines
+    value:           '10'
+  - key:             google-readability-namespace-comments.SpacesBeforeComments
+    value:           '2'
+...
+

.gitignore

@@ -56,6 +56,7 @@ tags
 CMakeFiles
 CMakeCache.txt
 cmake_install.cmake
+compile_commands.json
 
 # External Repos #
 ##################

CMakeLists.txt

@@ -1,6 +1,6 @@
 ###| CMAKE Kiibohd Controller |###
 #
-# Jacob Alexander 2011-2015
+# Jacob Alexander 2011-2016
 # Due to this file's usefulness:
 #
 # Released into the Public Domain
@@ -25,7 +25,8 @@ set( CHIP
 	"mk20dx128vlf5"    # McHCK       mk20dx128vlf5
 #       "mk20dx256"        # Teensy   3.1,3.2 (arm)
 #       "mk20dx256vlh7"    # Kiibohd-dfu mk20dx256vlh7
-	CACHE STRING "Microcontroller Chip" )
+	CACHE STRING "Microcontroller Chip"
+)
 
 
 
@@ -33,13 +34,14 @@ set( CHIP
 # Compiler Selection
 #
 
-#| *** EXPERIMENTAL ***
-#| Stick with gcc unless you know what you're doing
+#| gcc has been tested much more (and will likely give smaller binaries)
+#| clang does work though
 #| Currently only arm is supported with clang
 set( COMPILER
 	"gcc"   # arm-none-eabi-gcc / avr-gcc - Default
 #       "clang" # arm-none-eabi
-	CACHE STRING "Compiler Type" )
+	CACHE STRING "Compiler Type"
+)
 
 
 
@@ -72,11 +74,13 @@ set(  MacroModule "PartialMap"
 
 ##| Sends the current list of usb key codes through USB HID
 set( OutputModule "pjrcUSB"
-	CACHE STRING "Output Module" )
+	CACHE STRING "Output Module"
+)
 
 ##| Debugging source to use, each module has it's own set of defines that it sets
 set(  DebugModule "full"
-	CACHE STRING "Debug Module" )
+	CACHE STRING "Debug Module"
+)
 
 
 

Lib/CMake/arm.cmake

@@ -1,6 +1,6 @@
 ###| CMAKE Kiibohd Controller |###
 #
-# Jacob Alexander 2011-2014
+# Jacob Alexander 2011-2016
 # Due to this file's usefulness:
 #
 # Released into the Public Domain
@@ -111,6 +111,13 @@ set( COMPILER_SRCS
 	Lib/delay.c
 )
 
+#| Clang needs a few more functions for linking
+if ( "${COMPILER}" MATCHES "clang" )
+	set( COMPILER_SRCS ${COMPILER_SRCS}
+		Lib/clang.c
+	)
+endif ()
+
 message( STATUS "Compiler Source Files:" )
 message( "${COMPILER_SRCS}" )
 

Lib/CMake/build.cmake

@@ -135,3 +135,23 @@ elseif ( DEFINED TEENSY )
 	endif()
 endif()
 
+
+
+###
+# Compiler Command Generation
+#
+
+#| Generate list of compiler commands for clang-tidy usage
+set( CMAKE_EXPORT_COMPILE_COMMANDS ON )
+
+#| Make sure symlink exists (for convenience)
+if ( UNIX )
+	# Make sure symlink is created immediately
+	execute_process ( COMMAND ln -sfn ${CMAKE_BINARY_DIR}/compile_commands.json ${CMAKE_SOURCE_DIR}/. )
+
+	# Also update before each build
+	add_custom_command( TARGET ${TARGET_ELF} POST_BUILD
+		COMMAND ln -sfn ${CMAKE_BINARY_DIR}/compile_commands.json ${CMAKE_SOURCE_DIR}/.
+	)
+endif ()
+

Lib/clang.c

@@ -0,0 +1,61 @@
+/* Copyright (C) 2016 by Jacob Alexander
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+
+// This file adds various functions that clang doesn't link properly
+// AFAIK, clang doesn't have an elegant solution for this, so this is what we gotta do...
+
+// ----- Includes -----
+
+// Compiler Includes
+#include <string.h>
+
+
+void __aeabi_memcpy( void *dest, const void *src, size_t n )
+{
+	(void)memcpy(dest, src, n);
+}
+
+void __aeabi_memcpy4( void *dest, const void *src, size_t n )
+{
+	memcpy(dest, src, n);
+}
+
+void __aeabi_memclr( void *dest, size_t n )
+{
+	memset(dest, 0, n);
+}
+
+void __aeabi_memclr4( void *dest, size_t n )
+{
+	memset(dest, 0, n);
+}
+
+void __aeabi_memmove( void *dest, const void *src, size_t n )
+{
+	(void)memmove(dest, src, n);
+}
+
+void __aeabi_memset( void *s, size_t n, int c )
+{
+	(void)memset(s, c, n);
+}
+