diff --git a/compiler/rustc_builtin_macros/src/format.rs b/compiler/rustc_builtin_macros/src/format.rs index 3b7e2102ffa9b..bce466921d0ff 100644 --- a/compiler/rustc_builtin_macros/src/format.rs +++ b/compiler/rustc_builtin_macros/src/format.rs @@ -485,7 +485,7 @@ impl<'a, 'b> Context<'a, 'b> { if let Some(span) = fmt.width_span { let span = self.fmtsp.from_inner(InnerSpan::new(span.start, span.end)); match fmt.width { - parse::CountIsParam(pos) if pos > self.num_args() => { + parse::CountIsParam(pos) if pos >= self.num_args() => { e.span_label( span, &format!( diff --git a/src/test/ui/fmt/ifmt-bad-arg.rs b/src/test/ui/fmt/ifmt-bad-arg.rs index b3e54ed32aac7..84f4cc7f4ccd8 100644 --- a/src/test/ui/fmt/ifmt-bad-arg.rs +++ b/src/test/ui/fmt/ifmt-bad-arg.rs @@ -86,6 +86,9 @@ tenth number: {}", println!("{:foo}", 1); //~ ERROR unknown format trait `foo` println!("{5} {:4$} {6:7$}", 1); //~^ ERROR invalid reference to positional arguments 4, 5, 6 and 7 (there is 1 argument) + let foo = 1; + println!("{foo:0$}"); + //~^ ERROR invalid reference to positional argument 0 (no arguments were given) // We used to ICE here because we tried to unconditionally access the first argument, which // doesn't exist. diff --git a/src/test/ui/fmt/ifmt-bad-arg.stderr b/src/test/ui/fmt/ifmt-bad-arg.stderr index d181fe14107e7..5439ee173985b 100644 --- a/src/test/ui/fmt/ifmt-bad-arg.stderr +++ b/src/test/ui/fmt/ifmt-bad-arg.stderr @@ -251,8 +251,19 @@ LL | println!("{5} {:4$} {6:7$}", 1); = note: positional arguments are zero-based = note: for information about formatting flags, visit https://doc.rust-lang.org/std/fmt/index.html +error: invalid reference to positional argument 0 (no arguments were given) + --> $DIR/ifmt-bad-arg.rs:90:15 + | +LL | println!("{foo:0$}"); + | ^^^^^--^ + | | + | this width flag expects an `usize` argument at position 0, but no arguments were given + | + = note: positional arguments are zero-based + = note: for information about formatting flags, visit https://doc.rust-lang.org/std/fmt/index.html + error: 2 positional arguments in format string, but no arguments were given - --> $DIR/ifmt-bad-arg.rs:92:15 + --> $DIR/ifmt-bad-arg.rs:95:15 | LL | println!("{:.*}"); | ^^--^ @@ -328,7 +339,7 @@ LL | pub fn from_usize(x: &usize) -> ArgumentV1<'_> { | ^^^^^^^^^^ = note: this error originates in the macro `$crate::format_args_nl` which comes from the expansion of the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info) -error: aborting due to 36 previous errors +error: aborting due to 37 previous errors Some errors have detailed explanations: E0308, E0425. For more information about an error, try `rustc --explain E0308`.