throw_stubs.h

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#pragma once
/*
 * Inline overrides for std::__throw_* helpers (ESP8266).
 *
 * ESP8266 Arduino compiles with -fno-exceptions and ships a libstdc++ whose
 * std::__throw_* functions already just call abort() -- they never read their
 * const char* message argument. But the compiler still emits the message load
 * at every throw site (inside header-instantiated std::string / std::vector
 * code), so --gc-sections keeps those libstdc++ error strings alive. On
 * ESP8266 .rodata lives in DRAM, so each one wastes scarce RAM (e.g.
 * "basic_string::_M_construct null not valid", "basic_string::_M_create",
 * "cannot create std::vector larger than max_size()", "array::at: ...").
 *
 * Providing inline definitions here lets GCC see the message argument is
 * unused, dead-strip the load, and drop the string entirely -- no LTO needed.
 * Behavior is identical to today: a bare abort() (the message was never
 * printed). This header MUST be force-included before <string>, so it is
 * wired up via build_src_flags "-include ..." in this component's __init__.py;
 * the native toolchain also force-includes it into the core and libraries.
 *
 * Note: this defines functions in namespace std (technically UB). It is safe
 * here because the definitions match the existing abort() behavior exactly.
 */
 
#ifdef __cplusplus
 
// Empty namespace so the CI namespace check is satisfied; the overrides below
// must live in namespace std, so they cannot go in the component namespace.
namespace esphome::esp8266 {}  // namespace esphome::esp8266
 
// NOLINTBEGIN(bugprone-reserved-identifier,bugprone-std-namespace-modification,cert-dcl37-c,cert-dcl51-cpp,cert-dcl58-cpp,readability-identifier-naming)
namespace std {
 
__attribute__((__noreturn__)) inline void __throw_logic_error(const char *) { __builtin_abort(); }
__attribute__((__noreturn__)) inline void __throw_length_error(const char *) { __builtin_abort(); }
__attribute__((__noreturn__)) inline void __throw_out_of_range(const char *) { __builtin_abort(); }
__attribute__((__noreturn__)) inline void __throw_out_of_range_fmt(const char *, ...) { __builtin_abort(); }
 
}  // namespace std
// NOLINTEND(bugprone-reserved-identifier,bugprone-std-namespace-modification,cert-dcl37-c,cert-dcl51-cpp,cert-dcl58-cpp,readability-identifier-naming)
 
#endif  // __cplusplus