autofix-flag-cleaner

name	autofix-flag-cleaner
description	Removes unsupported or unknown compiler flags from build configurations.

Flag Cleaner Skill

Fixes build errors caused by compiler flags that are not supported by the current toolchain.

Detection Patterns

• unknown argument: '-fX'
• unsupported option '-fX'
• unknown warning option '-Wno-X'
• unrecognized command line option

Strategy

1. Extract Flag: Parse the unsupported flag from the error.
2. Locate Build File: Find where the flag is defined.
3. Remove Flag: Delete the flag from the build configuration.

Instructions

Step 1: Identify the Flag

From error: clang: error: unknown argument: '-fno-strict-overflow' Flag: -fno-strict-overflow

Step 2: Find the Build File

Search for the flag in build files:

grep -r "fno-strict-overflow" --include="*.bp" --include="*.gn" --include="CMakeLists.txt"

Step 3: Remove the Flag

In Android.bp:

// Before
cflags: ["-Wall", "-fno-strict-overflow", "-O2"],
// After
cflags: ["-Wall", "-O2"],

In BUILD.gn:

// Before
cflags = [ "-Wall", "-fno-strict-overflow" ]
// After  
cflags = [ "-Wall" ]

In CMakeLists.txt:

# Before
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-strict-overflow")
# After
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS}")

Common Problematic Flags

Flag	Issue
-fno-strict-overflow	GCC-only, not in Clang
-Wno-unused-but-set-*	GCC-only warning
-fstack-protector-strong	Older toolchains