@@ -158,56 +158,64 @@ pub const fn panic(expr: &'static str) -> ! {
158158// reducing binary size impact.
159159macro_rules! panic_const {
160160 ( $( $lang: ident = $message: expr, ) +) => {
161- pub mod panic_const {
162- use super :: * ;
163-
164- $(
165- /// This is a panic called with a message that's a result of a MIR-produced Assert.
166- //
167- // never inline unless panic_immediate_abort to avoid code
168- // bloat at the call sites as much as possible
169- #[ cfg_attr( not( feature = "panic_immediate_abort" ) , inline( never) , cold) ]
170- #[ cfg_attr( feature = "panic_immediate_abort" , inline) ]
171- #[ track_caller]
172- #[ rustc_const_unstable( feature = "panic_internals" , issue = "none" ) ]
173- #[ lang = stringify!( $lang) ]
174- pub const fn $lang( ) -> ! {
175- // Use Arguments::new_const instead of format_args!("{expr}") to potentially
176- // reduce size overhead. The format_args! macro uses str's Display trait to
177- // write expr, which calls Formatter::pad, which must accommodate string
178- // truncation and padding (even though none is used here). Using
179- // Arguments::new_const may allow the compiler to omit Formatter::pad from the
180- // output binary, saving up to a few kilobytes.
181- panic_fmt( fmt:: Arguments :: new_const( & [ $message] ) ) ;
182- }
183- ) +
184- }
161+ $(
162+ /// This is a panic called with a message that's a result of a MIR-produced Assert.
163+ //
164+ // never inline unless panic_immediate_abort to avoid code
165+ // bloat at the call sites as much as possible
166+ #[ cfg_attr( not( feature = "panic_immediate_abort" ) , inline( never) , cold) ]
167+ #[ cfg_attr( feature = "panic_immediate_abort" , inline) ]
168+ #[ track_caller]
169+ #[ rustc_const_unstable( feature = "panic_internals" , issue = "none" ) ]
170+ #[ lang = stringify!( $lang) ]
171+ pub const fn $lang( ) -> ! {
172+ // Use Arguments::new_const instead of format_args!("{expr}") to potentially
173+ // reduce size overhead. The format_args! macro uses str's Display trait to
174+ // write expr, which calls Formatter::pad, which must accommodate string
175+ // truncation and padding (even though none is used here). Using
176+ // Arguments::new_const may allow the compiler to omit Formatter::pad from the
177+ // output binary, saving up to a few kilobytes.
178+ panic_fmt( fmt:: Arguments :: new_const( & [ $message] ) ) ;
179+ }
180+ ) +
185181 }
186182}
187183
188- // Unfortunately this set of strings is replicated here and in a few places in the compiler in
189- // slightly different forms. It's not clear if there's a good way to deduplicate without adding
190- // special cases to the compiler (e.g., a const generic function wouldn't have a single definition
191- // shared across crates, which is exactly what we want here).
192- panic_const ! {
193- panic_const_add_overflow = "attempt to add with overflow" ,
194- panic_const_sub_overflow = "attempt to subtract with overflow" ,
195- panic_const_mul_overflow = "attempt to multiply with overflow" ,
196- panic_const_div_overflow = "attempt to divide with overflow" ,
197- panic_const_rem_overflow = "attempt to calculate the remainder with overflow" ,
198- panic_const_neg_overflow = "attempt to negate with overflow" ,
199- panic_const_shr_overflow = "attempt to shift right with overflow" ,
200- panic_const_shl_overflow = "attempt to shift left with overflow" ,
201- panic_const_div_by_zero = "attempt to divide by zero" ,
202- panic_const_rem_by_zero = "attempt to calculate the remainder with a divisor of zero" ,
203- panic_const_coroutine_resumed = "coroutine resumed after completion" ,
204- panic_const_async_fn_resumed = "`async fn` resumed after completion" ,
205- panic_const_async_gen_fn_resumed = "`async gen fn` resumed after completion" ,
206- panic_const_gen_fn_none = "`gen fn` should just keep returning `None` after completion" ,
207- panic_const_coroutine_resumed_panic = "coroutine resumed after panicking" ,
208- panic_const_async_fn_resumed_panic = "`async fn` resumed after panicking" ,
209- panic_const_async_gen_fn_resumed_panic = "`async gen fn` resumed after panicking" ,
210- panic_const_gen_fn_none_panic = "`gen fn` should just keep returning `None` after panicking" ,
184+ pub mod panic_const {
185+ use super :: * ;
186+ // Unfortunately this set of strings is replicated here and in a few places in the compiler in
187+ // slightly different forms. It's not clear if there's a good way to deduplicate without adding
188+ // special cases to the compiler (e.g., a const generic function wouldn't have a single definition
189+ // shared across crates, which is exactly what we want here).
190+ panic_const ! {
191+ panic_const_add_overflow = "attempt to add with overflow" ,
192+ panic_const_sub_overflow = "attempt to subtract with overflow" ,
193+ panic_const_mul_overflow = "attempt to multiply with overflow" ,
194+ panic_const_div_overflow = "attempt to divide with overflow" ,
195+ panic_const_rem_overflow = "attempt to calculate the remainder with overflow" ,
196+ panic_const_neg_overflow = "attempt to negate with overflow" ,
197+ panic_const_shr_overflow = "attempt to shift right with overflow" ,
198+ panic_const_shl_overflow = "attempt to shift left with overflow" ,
199+ panic_const_div_by_zero = "attempt to divide by zero" ,
200+ panic_const_rem_by_zero = "attempt to calculate the remainder with a divisor of zero" ,
201+ panic_const_coroutine_resumed = "coroutine resumed after completion" ,
202+ panic_const_async_fn_resumed = "`async fn` resumed after completion" ,
203+ panic_const_async_gen_fn_resumed = "`async gen fn` resumed after completion" ,
204+ panic_const_gen_fn_none = "`gen fn` should just keep returning `None` after completion" ,
205+ panic_const_coroutine_resumed_panic = "coroutine resumed after panicking" ,
206+ panic_const_async_fn_resumed_panic = "`async fn` resumed after panicking" ,
207+ panic_const_async_gen_fn_resumed_panic = "`async gen fn` resumed after panicking" ,
208+ panic_const_gen_fn_none_panic = "`gen fn` should just keep returning `None` after panicking" ,
209+ }
210+ // Separated panic constants list for async drop feature
211+ // (May be joined when the corresponding lang items will be in the bootstrap)
212+ #[ cfg( not( bootstrap) ) ]
213+ panic_const ! {
214+ panic_const_coroutine_resumed_drop = "coroutine resumed after async drop" ,
215+ panic_const_async_fn_resumed_drop = "`async fn` resumed after async drop" ,
216+ panic_const_async_gen_fn_resumed_drop = "`async gen fn` resumed after async drop" ,
217+ panic_const_gen_fn_none_drop = "`gen fn` resumed after async drop" ,
218+ }
211219}
212220
213221/// Like `panic`, but without unwinding and track_caller to reduce the impact on codesize on the caller.
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