Brief description

Clang-based standalone tool that diagnoses the following cases of defining functions:

• completely unused functions declared as extern;
• functions declared as extern which are used only locally and thus can be made static.

Example

Input:

static void firstStatic(void);
static void secondStatic(void);

void firstExtern(void);

extern void secondExtern(void);

static void firstStatic(void)  { }
static void secondStatic(void) { }

void firstExtern(void)  { }
void secondExtern(void) { }

int
main(void)
{
    firstExtern();
    secondStatic();
    return 0;
}

Run command:

bin/unused-funcs main.c --

Output (paths are truncated):

.../main.c:20:firstExtern:can be made static
.../main.c:25:secondExtern:unused

Building

1. Clone the repository to llvm/tools/clang/tools/extra.
2. Add add_subdirectory(unused-funcs) to CMakeLists.txt in the same directory.
3. Run ninja unused-funcs inside your LLVM's build/ directory.