use config.json instead

Author: SchrodingerZhu

libc/CMakeLists.txt

@@ -47,10 +47,6 @@ set(LIBC_NAMESPACE ${default_namespace}
   CACHE STRING "The namespace to use to enclose internal implementations. Must start with '__llvm_libc'."
 )
 
-# Codegen options.
-option(LLVM_LIBC_KEEP_FRAME_POINTER "Keep frame pointers in LLVM libc" ON)
-option(LLVM_LIBC_ENABLE_STACK_PROTECTOR "Enable stack protector for LLVM libc" ON)
-
 if(LLVM_LIBC_FULL_BUILD OR LLVM_LIBC_GPU_BUILD)
   if(NOT LIBC_HDRGEN_EXE)
     # We need to set up hdrgen first since other targets depend on it.

libc/cmake/modules/LLVMLibCCompileOptionRules.cmake

@@ -60,13 +60,13 @@ function(_get_common_compile_options output_var flags)
     if (LIBC_CC_SUPPORTS_PATTERN_INIT)
       list(APPEND compile_options "-ftrivial-auto-var-init=pattern")
     endif()
-    if (LLVM_LIBC_KEEP_FRAME_POINTER)
+    if (LIBC_CONF_KEEP_FRAME_POINTER)
       list(APPEND compile_options "-fno-omit-frame-pointer")
       if (LIBC_TARGET_ARCHITECTURE_IS_X86)
         list(APPEND compile_options "-mno-omit-leaf-frame-pointer")
       endif()
     endif()
-    if (LLVM_LIBC_ENABLE_STACK_PROTECTOR)
+    if (LIBC_CONF_ENABLE_STACK_PROTECTOR)
       list(APPEND compile_options "-fstack-protector-strong")
     endif()
     list(APPEND compile_options "-Wall")

libc/config/config.json

@@ -30,5 +30,15 @@
       "value": false,
       "doc": "Inserts prefetch for write instructions (PREFETCHW) for memset on x86 to recover performance when hardware prefetcher is disabled."
     }
+  },
+  "codegen": {
+    "LIBC_CONF_KEEP_FRAME_POINTER": {
+      "value": true,
+      "doc": "Keep frame pointer in functions for better debugging experience."
+    },
+    "LIBC_CONF_ENABLE_STRONG_STACK_PROTECTOR": {
+      "value": true,
+      "doc": "Enable -fstack-protector-strong to defend against stack smashing attack."
+    }
   }
 }

libc/docs/configure.rst

@@ -25,6 +25,9 @@ See the main ``config/config.json``, and the platform and architecture specific
 overrides in ``config/<platform>/config.json`` and ``config/<platform>/<arch>/config.json,``
 to learn about the defaults for your platform and target.
 
+* **"codegen" options**
+    - ``LIBC_CONF_ENABLE_STRONG_STACK_PROTECTOR``: Enable -fstack-protector-strong to defend against stack smashing attack.
+    - ``LIBC_CONF_KEEP_FRAME_POINTER``: Keep frame pointer in functions for better debugging experience.
 * **"printf" options**
     - ``LIBC_CONF_PRINTF_DISABLE_FIXED_POINT``: Disable printing fixed point values in printf and friends.
     - ``LIBC_CONF_PRINTF_DISABLE_FLOAT``: Disable printing floating point values in printf and friends.