From a9d2cba0c5fdb8b257c2b4405806666978785cc2 Mon Sep 17 00:00:00 2001
From: "copilot-swe-agent[bot]" <198982749+Copilot@users.noreply.github.com>
Date: Sun, 28 Dec 2025 21:59:29 +0000
Subject: [PATCH] Add Clang compiler support alongside GCC

Co-authored-by: johndoe6345789 <224850594+johndoe6345789@users.noreply.github.com>
---
 CMakeLists.txt            | 11 +++++++++++
 README.md                 | 18 ++++++++++++++++++
 bootloader/CMakeLists.txt | 21 +++++++++++++++------
 kernel/CMakeLists.txt     | 31 ++++++++++++++++++++++++++-----
 4 files changed, 70 insertions(+), 11 deletions(-)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0888c4a..563a655 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -18,6 +18,17 @@ set(CMAKE_CXX_STANDARD_REQUIRED ON)
 # Export compile commands for IDE support
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
+# Compiler detection and configuration
+if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+    message(STATUS "Using Clang compiler")
+    set(USING_CLANG TRUE)
+elseif(CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
+    message(STATUS "Using GCC compiler")
+    set(USING_GCC TRUE)
+else()
+    message(WARNING "Unsupported compiler: ${CMAKE_CXX_COMPILER_ID}")
+endif()
+
 # Default to Release build if not specified
 if(NOT CMAKE_BUILD_TYPE)
     set(CMAKE_BUILD_TYPE Release CACHE STRING "Build type" FORCE)
diff --git a/README.md b/README.md
index 95d45af..3868ef9 100644
--- a/README.md
+++ b/README.md
@@ -87,6 +87,24 @@ ninja
 ninja qemu
 ```
 
+### Building with Clang
+
+MetalOS supports both GCC and Clang compilers. To build with Clang:
+
+```bash
+mkdir build && cd build
+CC=clang CXX=clang++ cmake ..
+cmake --build .
+```
+
+Or with Ninja:
+
+```bash
+mkdir build && cd build
+CC=clang CXX=clang++ cmake -G Ninja ..
+ninja
+```
+
 ### Conan (With Package Management)
 
 ```bash
diff --git a/bootloader/CMakeLists.txt b/bootloader/CMakeLists.txt
index 627aa12..fb73049 100644
--- a/bootloader/CMakeLists.txt
+++ b/bootloader/CMakeLists.txt
@@ -30,12 +30,21 @@ set(UEFI_CFLAGS
 )
 
 # Linker flags for UEFI
-set(UEFI_LDFLAGS
-    -shared
-    -Bsymbolic
-    -nostdlib
-    -znocombreloc
-)
+if(CMAKE_C_COMPILER_ID MATCHES "Clang")
+    set(UEFI_LDFLAGS
+        -shared
+        -Bsymbolic
+        -nostdlib
+        -Wl,-z,nocombreloc
+    )
+else()
+    set(UEFI_LDFLAGS
+        -shared
+        -Bsymbolic
+        -nostdlib
+        -znocombreloc
+    )
+endif()
 
 # Create object library
 add_library(bootloader_obj OBJECT ${BOOTLOADER_SOURCES})
diff --git a/kernel/CMakeLists.txt b/kernel/CMakeLists.txt
index cef35e1..618cdd8 100644
--- a/kernel/CMakeLists.txt
+++ b/kernel/CMakeLists.txt
@@ -55,6 +55,16 @@ set(KERNEL_CXXFLAGS
     -O2
 )
 
+# Add Clang-specific flags
+if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+    list(APPEND KERNEL_CXXFLAGS
+        -target x86_64-unknown-none-elf
+        -fno-builtin
+        -fno-pie
+    )
+    message(STATUS "Added Clang-specific flags for kernel")
+endif()
+
 # Create object library
 add_library(kernel_obj OBJECT ${KERNEL_SOURCES})
 target_include_directories(kernel_obj PRIVATE include)
@@ -67,11 +77,22 @@ set_target_properties(kernel_elf PROPERTIES
     LINKER_LANGUAGE CXX
     POSITION_INDEPENDENT_CODE OFF
 )
-target_link_options(kernel_elf PRIVATE
-    -nostdlib
-    -no-pie
-    -T ${CMAKE_CURRENT_SOURCE_DIR}/linker.ld
-)
+
+# Set linker options based on compiler
+if(CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+    target_link_options(kernel_elf PRIVATE
+        -nostdlib
+        -Wl,--no-pie
+        -T ${CMAKE_CURRENT_SOURCE_DIR}/linker.ld
+        -target x86_64-unknown-none-elf
+    )
+else()
+    target_link_options(kernel_elf PRIVATE
+        -nostdlib
+        -no-pie
+        -T ${CMAKE_CURRENT_SOURCE_DIR}/linker.ld
+    )
+endif()
 
 # Custom command to create flat binary
 add_custom_command(