Compile Args

Overview

Manages compiler arguments passed to libclang for parsing. Controls language standard, preprocessor defines, include paths, and target configuration.

Why Use This?

libclang requires explicit compiler flags to parse code correctly. This class provides a fluent builder API instead of raw argument string construction, and ensures compatibility across platforms and compilers.

Types

Type	Description
compile_args	Fluent builder for compiler arguments
language_standard	Enum of supported C/C++ standards (c89 through cxx26)
language_mode	Enum of language modes (c, cxx, objective_c, objective_cxx)

Functions

compile_args()

Default constructor. Creates empty argument list.

add

Add a raw compiler argument.

Signature: void add(const std::string& arg)

Parameters:

• arg — raw compiler flag (e.g., -Wall)

add_many

Add multiple raw compiler arguments.

Signature: void add_many(const std::vector<std::string>& args_to_add)

Parameters:

• args_to_add — list of raw compiler flags

clear

Remove all arguments.

Signature: void clear()

get_args

Get the current argument list.

Signature: const std::vector<std::string>& get_args() const

Returns: reference to the internal argument vector

set_standard

Set the language standard.

Signature: compile_args& set_standard(language_standard std)

Parameters:

• std — language standard enum value (e.g., language_standard::cxx20)

Returns: *this for chaining

set_language

Set the language mode.

Signature: compile_args& set_language(language_mode lang)

Parameters:

• lang — language mode (e.g., language_mode::cxx)

Returns: *this for chaining

add_include_path

Add a single include path (-I<path>).

Signature: compile_args& add_include_path(const std::string& path)

Parameters:

• path — include directory path

Returns: *this for chaining

add_include_paths

Add multiple include paths.

Signature: compile_args& add_include_paths(const std::vector<std::string>& paths)

Parameters:

• paths — list of include directory paths

Returns: *this for chaining

define

Define a preprocessor macro.

Signatures:

• compile_args& define(const std::string& name) — define flag (-D<name>)
• compile_args& define(const std::string& name, const std::string& value) — define with string value
• compile_args& define(const std::string& name, int value) — define with integer value

Parameters:

• name — macro name
• value — macro value (optional)

Returns: *this for chaining

undefine

Undefine a preprocessor macro (-U<name>).

Signature: compile_args& undefine(const std::string& name)

Parameters:

• name — macro name to undefine

Returns: *this for chaining

set_target

Set target triple for cross-compilation (--target=<triple>).

Signature: compile_args& set_target(const std::string& triple)

Parameters:

• triple — target triple (e.g., "x86_64-linux-gnu", "aarch64-linux-gnu")

Returns: *this for chaining

Notes: Affects sizeof, predefined macros, and type alignment.

set_pointer_size

Set pointer size for cross-compilation (-m32 or -m64).

Signature: compile_args& set_pointer_size(int bits)

Parameters:

• bits — pointer size in bits (32 or 64)

Returns: *this for chaining

modern_cxx (static)

Create a preset configured for modern C++ development.

Signature: static compile_args modern_cxx(language_standard std = language_standard::cxx20)

Parameters:

• std — C++ standard to use (default: C++20)

Returns: configured compile_args instance

modern_c (static)

Create a preset configured for C development.

Signature: static compile_args modern_c(language_standard std = language_standard::c17)

Parameters:

• std — C standard to use (default: C17)

Returns: configured compile_args instance

minimal (static)

Create a preset with no default flags.

Signature: static compile_args minimal()

Returns: empty compile_args instance

Example:

auto args = xccmeta::compile_args::modern_cxx();
args.define("DEBUG", "1")
    .add_include_path("/opt/custom/include")
    .set_target("aarch64-linux-gnu");