Rollup merge of #90131 - camsteffen:fmt-args-span-fix, r=cjgillot

Fix a format_args span to be expansion

I found this while exploring solutions for rust-lang/rust-clippy#7843.

r? `@m-ou-se`

Author: matthiaskrgr

compiler/rustc_builtin_macros/src/format.rs

@@ -769,7 +769,10 @@ impl<'a, 'b> Context<'a, 'b> {
             for arg_ty in self.arg_unique_types[i].iter() {
                 args.push(Context::format_arg(self.ecx, self.macsp, e.span, arg_ty, i));
             }
-            heads.push(self.ecx.expr_addr_of(e.span, e));
+            // use the arg span for `&arg` so that borrowck errors
+            // point to the specific expression passed to the macro
+            // (the span is otherwise unavailable in MIR)
+            heads.push(self.ecx.expr_addr_of(e.span.with_ctxt(self.macsp.ctxt()), e));
         }
         for pos in self.count_args {
             let index = match pos {

src/test/ui/borrowck/borrowck-and-init.stderr

@@ -3,6 +3,8 @@ error[E0381]: borrow of possibly-uninitialized variable: `i`
    |
 LL |     println!("{}", i);
    |                    ^ use of possibly-uninitialized `i`
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/borrowck/borrowck-break-uninit-2.stderr

@@ -3,6 +3,8 @@ error[E0381]: borrow of possibly-uninitialized variable: `x`
    |
 LL |     println!("{}", x);
    |                    ^ use of possibly-uninitialized `x`
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/borrowck/borrowck-break-uninit.stderr

@@ -3,6 +3,8 @@ error[E0381]: borrow of possibly-uninitialized variable: `x`
    |
 LL |     println!("{}", x);
    |                    ^ use of possibly-uninitialized `x`
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/borrowck/borrowck-or-init.stderr

@@ -3,6 +3,8 @@ error[E0381]: borrow of possibly-uninitialized variable: `i`
    |
 LL |     println!("{}", i);
    |                    ^ use of possibly-uninitialized `i`
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/borrowck/borrowck-while-break.stderr

@@ -3,6 +3,8 @@ error[E0381]: borrow of possibly-uninitialized variable: `v`
    |
 LL |     println!("{}", v);
    |                    ^ use of possibly-uninitialized `v`
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/borrowck/issue-24267-flow-exit.stderr

@@ -3,12 +3,16 @@ error[E0381]: borrow of possibly-uninitialized variable: `x`
    |
 LL |     println!("{}", x);
    |                    ^ use of possibly-uninitialized `x`
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0381]: borrow of possibly-uninitialized variable: `x`
   --> $DIR/issue-24267-flow-exit.rs:18:20
    |
 LL |     println!("{}", x);
    |                    ^ use of possibly-uninitialized `x`
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to 2 previous errors
 

src/test/ui/closures/2229_closure_analysis/diagnostics/arrays.stderr

@@ -81,6 +81,8 @@ LL |     println!("{}", arr[3]);
 ...
 LL |     c();
    |     - mutable borrow later used here
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0502]: cannot borrow `arr` as immutable because it is also borrowed as mutable
   --> $DIR/arrays.rs:73:24

src/test/ui/closures/2229_closure_analysis/diagnostics/box.stderr

@@ -25,6 +25,8 @@ LL |     println!("{}", e.0.0.m.x);
 LL |
 LL |     c();
    |     - mutable borrow later used here
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0506]: cannot assign to `e.0.0.m.x` because it is borrowed
   --> $DIR/box.rs:55:5

src/test/ui/closures/2229_closure_analysis/diagnostics/repr_packed.stderr

@@ -8,6 +8,7 @@ LL |         println!("{}", foo.x);
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #82523 <https://github.com/rust-lang/rust/issues/82523>
    = note: fields of packed structs are not properly aligned, and creating a misaligned reference is undefined behavior (even if that reference is never dereferenced)
+   = note: this warning originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 warning: 1 warning emitted
 

src/test/ui/closures/2229_closure_analysis/diagnostics/simple-struct-min-capture.stderr

@@ -13,6 +13,8 @@ LL |     println!("{:?}", p);
 LL |
 LL |     c();
    |     - mutable borrow later used here
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/codemap_tests/tab_3.stderr

@@ -14,6 +14,7 @@ note: this function takes ownership of the receiver `self`, which moves `some_ve
    |
 LL |     fn into_iter(self) -> Self::IntoIter;
    |                  ^^^^
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/consts/const-eval/conditional_array_execution.stderr

@@ -28,6 +28,7 @@ LL |     println!("{}", FOO);
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>
+   = note: this warning originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error; 2 warnings emitted
 

src/test/ui/consts/const-eval/issue-43197.stderr

@@ -39,6 +39,7 @@ LL |     println!("{} {}", X, Y);
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>
+   = note: this warning originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0080]: evaluation of constant value failed
   --> $DIR/issue-43197.rs:16:26
@@ -54,6 +55,7 @@ LL |     println!("{} {}", X, Y);
    |
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>
+   = note: this warning originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to 2 previous errors; 4 warnings emitted
 

src/test/ui/generator/yield-while-ref-reborrowed.stderr

@@ -10,6 +10,8 @@ LL |     println!("{}", x);
    |                    ^ second borrow occurs here
 LL |     Pin::new(&mut b).resume(());
    |              ------ first borrow later used here
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/issues/issue-42796.stderr

@@ -8,6 +8,8 @@ LL |     let mut s_copy = s;
 ...
 LL |     println!("{}", s);
    |                    ^ value borrowed here after move
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/issues/issue-47646.stderr

@@ -12,6 +12,8 @@ LL |             println!("{:?}", heap);
 ...
 LL |     };
    |      - ... and the mutable borrow might be used here, when that temporary is dropped and runs the destructor for type `(Option<PeekMut<'_, i32>>, ())`
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/limits/issue-55878.stderr

@@ -18,6 +18,7 @@ LL |     println!("Size: {}", std::mem::size_of::<[u8; u64::MAX as usize]>());
    = note: `#[deny(const_err)]` on by default
    = warning: this was previously accepted by the compiler but is being phased out; it will become a hard error in a future release!
    = note: for more information, see issue #71800 <https://github.com/rust-lang/rust/issues/71800>
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to 2 previous errors
 

src/test/ui/liveness/liveness-move-in-while.stderr

@@ -28,6 +28,8 @@ LL |         println!("{}", y);
    |                        ^ value borrowed here after move
 LL |         while true { while true { while true { x = y; x.clone(); } } }
    |                                                    - value moved here, in previous iteration of loop
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error; 3 warnings emitted
 

src/test/ui/liveness/liveness-use-after-move.stderr

@@ -8,6 +8,8 @@ LL |     let y = x;
 LL | 
 LL |     println!("{}", *x);
    |                    ^^ value borrowed here after move
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/liveness/liveness-use-after-send.stderr

@@ -7,6 +7,8 @@ LL |     send(ch, message);
    |              ------- value moved here
 LL |     println!("{}", message);
    |                    ^^^^^^^ value borrowed here after move
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/loops/loop-proper-liveness.stderr

@@ -3,6 +3,8 @@ error[E0381]: borrow of possibly-uninitialized variable: `x`
    |
 LL |     println!("{:?}", x);
    |                      ^ use of possibly-uninitialized `x`
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/moves/moves-based-on-type-capture-clause-bad.stderr

@@ -10,6 +10,8 @@ LL |         println!("{}", x);
 LL |     });
 LL |     println!("{}", x);
    |                    ^ value borrowed here after move
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/try-block/try-block-maybe-bad-lifetime.stderr

@@ -21,6 +21,8 @@ LL |             ::std::mem::drop(x);
 LL |         };
 LL |         println!("{}", x);
    |                        ^ value borrowed here after move
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0506]: cannot assign to `i` because it is borrowed
   --> $DIR/try-block-maybe-bad-lifetime.rs:40:9

src/test/ui/use/use-after-move-based-on-type.stderr

@@ -7,6 +7,8 @@ LL |     let _y = x;
    |              - value moved here
 LL |     println!("{}", x);
    |                    ^ value borrowed here after move
+   |
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error
 

src/test/ui/walk-struct-literal-with.stderr

@@ -13,6 +13,7 @@ note: this function takes ownership of the receiver `self`, which moves `start`
    |
 LL |     fn make_string_bar(mut self) -> Mine{
    |                            ^^^^
+   = note: this error originates in the macro `$crate::format_args_nl` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to previous error