//! Before #78122, writing any `fmt::Arguments` would trigger the inclusion of `usize` formatting //! and padding code in the resulting binary, because indexing used in `fmt::write` would generate //! code using `panic_bounds_check`, which prints the index and length. //! //! These bounds checks are not necessary, as `fmt::Arguments` never contains any out-of-bounds //! indexes. The test is a `run-make` test, because it needs to check the result after linking. A //! codegen or assembly test doesn't check the parts that will be pulled in from `core` by the //! linker. //! //! In this test, we try to check that the `usize` formatting and padding code are not present in //! the final binary by checking that panic symbols such as `panic_bounds_check` are **not** //! present. //! //! Some CI jobs try to run faster by disabling debug assertions (through setting //! `NO_DEBUG_ASSERTIONS=1`). If debug assertions are disabled, then we can check for the absence of //! additional `usize` formatting and padding related symbols. //@ ignore-cross-compile use run_make_support::artifact_names::bin_name; use run_make_support::env::std_debug_assertions_enabled; use run_make_support::rustc; use run_make_support::symbols::object_contains_any_symbol_substring; fn main() { rustc().input("main.rs").opt().run(); // panic machinery identifiers, these should not appear in the final binary let mut panic_syms = vec!["panic_bounds_check", "Debug"]; if std_debug_assertions_enabled() { // if debug assertions are allowed, we need to allow these, // otherwise, add them to the list of symbols to deny. panic_syms.extend_from_slice(&["panicking", "panic_fmt", "pad_integral", "Display"]); } assert!(!object_contains_any_symbol_substring(bin_name("main"), &panic_syms)); }