[CMake] Look for clang-format only if UR_FORMAT_CPP_STYLE is on

CMakeLists.txt

@@ -130,18 +130,15 @@ if(UR_USE_MSAN)
     add_sanitizer_flag(memory)
 endif()
 
-find_program(CLANG_FORMAT NAMES clang-format-15 clang-format-15.0 clang-format)
-
-set(CLANG_FORMAT_REQUIRED "15.0")
+# Check if clang-format (in correct version) is available for Cpp code formatting.
+if(UR_FORMAT_CPP_STYLE)
+    find_program(CLANG_FORMAT NAMES clang-format-15 clang-format-15.0 clang-format)
 
-if(CLANG_FORMAT)
-    get_program_version_major_minor(${CLANG_FORMAT} CLANG_FORMAT_VERSION)
-    message(STATUS "Found clang-format: ${CLANG_FORMAT} (version: ${CLANG_FORMAT_VERSION})")
-endif()
+    if(CLANG_FORMAT)        
+        get_program_version_major_minor(${CLANG_FORMAT} CLANG_FORMAT_VERSION)
+        message(STATUS "Found clang-format: ${CLANG_FORMAT} (version: ${CLANG_FORMAT_VERSION})")
 
-# Check if the correct version of clang-format is available
-if(UR_FORMAT_CPP_STYLE)
-    if(CLANG_FORMAT)
+        set(CLANG_FORMAT_REQUIRED "15.0")
         if(NOT (CLANG_FORMAT_VERSION VERSION_EQUAL CLANG_FORMAT_REQUIRED))
             message(FATAL_ERROR "required clang-format version is ${CLANG_FORMAT_REQUIRED}")
         endif()

README.md

@@ -14,6 +14,7 @@
     - [Weekly tags](#weekly-tags)
 3. [Third-Party tools](#third-party-tools)
 4. [Building](#building)
+    - [Requirements](#requirements)
     - [Windows](#windows)
     - [Linux](#linux)
     - [CMake standard options](#cmake-standard-options)
@@ -71,9 +72,13 @@ Tools can be acquired via instructions in [third_party](/third_party/README.md).
 
 ## Building
 
-Requirements:
+### Requirements
+
+Required packages:
 - C++ compiler with C++17 support
 - [CMake](https://cmake.org/) >= 3.14.0
+
+For development and contributions:
 - clang-format-15.0 (can be installed with `python -m pip install clang-format==15.0.7`)
 
 ### Windows