From 98c8c5b3449457efd163089a3392c91f58496381 Mon Sep 17 00:00:00 2001
From: Carter Li <zhangsongcui3371@sina.com>
Date: Mon, 13 Jul 2026 10:18:01 +0800
Subject: [PATCH] CMake (Linux): detects MUSL automatically

---
 CMakeLists.txt | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 56ef392e0..59e46817a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -182,6 +182,26 @@ endif()
 
 set(WARNING_FLAGS "-Wall -Wextra -Wconversion -Werror=uninitialized -Werror=return-type -Werror=vla")
 
+if(LINUX)
+    if(NOT IS_MUSL) # `NOT DEFINED IS_MUSL` doesn't work
+        execute_process(
+            COMMAND ${CMAKE_C_COMPILER} -print-file-name=libc.so
+            OUTPUT_VARIABLE LIBC_PATH
+            OUTPUT_STRIP_TRAILING_WHITESPACE
+        )
+
+        if(LIBC_PATH MATCHES "-musl")
+            set(IS_MUSL ON CACHE BOOL "Build with musl libc" FORCE)
+        endif()
+    endif()
+
+    if(IS_MUSL)
+        message(STATUS "MUSL libc detected")
+        # Silence ioctl related warnings
+        set(WARNING_FLAGS "${WARNING_FLAGS} -Wno-sign-conversion")
+    endif()
+endif()
+
 set(CMAKE_C_STANDARD 23)
 set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${WARNING_FLAGS} -Werror=incompatible-pointer-types -Werror=implicit-function-declaration -Werror=int-conversion")