Do not mention -Zmacro-backtrace for std macros that are a wrapper around a compiler intrinsic

Author: estebank

compiler/rustc_expand/src/base.rs

@@ -851,6 +851,7 @@ pub struct SyntaxExtension {
     /// Should debuginfo for the macro be collapsed to the outermost expansion site (in other
     /// words, was the macro definition annotated with `#[collapse_debuginfo]`)?
     pub collapse_debuginfo: bool,
+    pub hide_backtrace: bool,
 }
 
 impl SyntaxExtension {
@@ -884,6 +885,7 @@ impl SyntaxExtension {
             allow_internal_unsafe: false,
             local_inner_macros: false,
             collapse_debuginfo: false,
+            hide_backtrace: false,
         }
     }
 
@@ -939,6 +941,12 @@ impl SyntaxExtension {
         collapse_table[flag as usize][attr as usize]
     }
 
+    fn get_hide_backtrace(attrs: &[hir::Attribute]) -> bool {
+        // FIXME(estebank): instead of reusing `#[rustc_diagnostic_item]` as a proxy, introduce a
+        // new attribute purely for this under the `#[diagnostic]` namespace.
+        ast::attr::find_by_name(attrs, sym::rustc_diagnostic_item).is_some()
+    }
+
     /// Constructs a syntax extension with the given properties
     /// and other properties converted from attributes.
     pub fn new(
@@ -975,6 +983,7 @@ impl SyntaxExtension {
             // Not a built-in macro
             None => (None, helper_attrs),
         };
+        let hide_backtrace = builtin_name.is_some() || Self::get_hide_backtrace(attrs);
 
         let stability = find_attr!(attrs, AttributeKind::Stability { stability, .. } => *stability);
 
@@ -1009,6 +1018,7 @@ impl SyntaxExtension {
             allow_internal_unsafe,
             local_inner_macros,
             collapse_debuginfo,
+            hide_backtrace,
         }
     }
 
@@ -1088,7 +1098,7 @@ impl SyntaxExtension {
             self.allow_internal_unsafe,
             self.local_inner_macros,
             self.collapse_debuginfo,
-            self.builtin_name.is_some(),
+            self.hide_backtrace,
         )
     }
 }

src/tools/miri/tests/fail/erroneous_const2.stderr

@@ -23,8 +23,6 @@ note: erroneous constant encountered
    |
 LL |     println!("{}", FOO);
    |                    ^^^
-   |
-   = note: this note 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 1 previous error
 

src/tools/miri/tests/pass/alloc-access-tracking.stderr

@@ -15,8 +15,6 @@ note: read access at ALLOC[0..1]
    |
 LL |         assert_eq!(*ptr, 42);
    |         ^^^^^^^^^^^^^^^^^^^^ tracking was triggered here
-   |
-   = note: this note originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 note: freed allocation ALLOC
   --> RUSTLIB/alloc/src/boxed.rs:LL:CC

tests/ui/asm/aarch64/type-check-2.stderr

@@ -21,7 +21,6 @@ LL |         asm!("{}", in(reg) vec![0]);
    |                            ^^^^^^^
    |
    = note: only integers, floats, SIMD vectors, pointers and function pointers can be used as arguments for inline assembly
-   = note: this error originates in the macro `vec` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: cannot use value of type `(i32, i32, i32)` for inline assembly
   --> $DIR/type-check-2.rs:36:28

tests/ui/asm/parse-error.stderr

@@ -193,16 +193,12 @@ error: asm template must be a string literal
    |
 LL |         asm!(format!("{{{}}}", 0), in(reg) foo);
    |              ^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: this error originates in the macro `format` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: asm template must be a string literal
   --> $DIR/parse-error.rs:86:21
    |
 LL |         asm!("{1}", format!("{{{}}}", 0), in(reg) foo, out(reg) bar);
    |                     ^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: this error originates in the macro `format` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: _ cannot be used for input operands
   --> $DIR/parse-error.rs:88:28
@@ -357,16 +353,12 @@ error: asm template must be a string literal
    |
 LL | global_asm!(format!("{{{}}}", 0), const FOO);
    |             ^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: this error originates in the macro `format` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: asm template must be a string literal
   --> $DIR/parse-error.rs:143:20
    |
 LL | global_asm!("{1}", format!("{{{}}}", 0), const FOO, const BAR);
    |                    ^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: this error originates in the macro `format` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: the `in` operand cannot be used with `global_asm!`
   --> $DIR/parse-error.rs:146:19

tests/ui/associated-consts/defaults-not-assumed-fail.stderr

@@ -23,8 +23,6 @@ note: erroneous constant encountered
    |
 LL |     assert_eq!(<() as Tr>::B, 0);    // causes the error above
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: this note originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 note: erroneous constant encountered
   --> $DIR/defaults-not-assumed-fail.rs:34:5
@@ -33,7 +31,6 @@ LL |     assert_eq!(<() as Tr>::B, 0);    // causes the error above
    |     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
    |
    = note: duplicate diagnostic emitted due to `-Z deduplicate-diagnostics=no`
-   = note: this note originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to 1 previous error
 

tests/ui/async-await/unreachable-lint-2.stderr

@@ -11,7 +11,6 @@ note: the lint level is defined here
    |
 LL | #![deny(unreachable_code)]
    |         ^^^^^^^^^^^^^^^^
-   = note: this error originates in the macro `println` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to 1 previous error
 

tests/ui/binop/binary-operation-error-on-function-70724.stderr

@@ -6,8 +6,6 @@ LL |     assert_eq!(a, 0);
    |     |
    |     fn() -> i32 {a}
    |     {integer}
-   |
-   = note: this error originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0308]: mismatched types
   --> $DIR/binary-operation-error-on-function-70724.rs:7:5
@@ -17,7 +15,6 @@ LL |     assert_eq!(a, 0);
    |
    = note: expected fn item `fn() -> i32 {a}`
                  found type `{integer}`
-   = note: this error originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0277]: `fn() -> i32 {a}` doesn't implement `Debug`
   --> $DIR/binary-operation-error-on-function-70724.rs:7:5
@@ -29,7 +26,6 @@ LL |     assert_eq!(a, 0);
    |     ^^^^^^^^^^^^^^^^ the trait `Debug` is not implemented for fn item `fn() -> i32 {a}`
    |
    = help: use parentheses to call this function: `a()`
-   = note: this error originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to 3 previous errors
 

tests/ui/binop/eq-vec.stderr

@@ -12,7 +12,6 @@ note: an implementation of `PartialEq` might be missing for `Foo`
    |
 LL |     enum Foo {
    |     ^^^^^^^^ must implement `PartialEq`
-   = note: this error originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 help: consider annotating `Foo` with `#[derive(PartialEq)]`
    |
 LL +     #[derive(PartialEq)]

tests/ui/binop/function-comparison-errors-59488.stderr

@@ -80,24 +80,18 @@ LL |     assert_eq!(Foo::Bar, i);
    |     |
    |     fn(usize) -> Foo {Foo::Bar}
    |     fn(usize) -> Foo {Foo::Bar}
-   |
-   = note: this error originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0277]: `fn(usize) -> Foo {Foo::Bar}` doesn't implement `Debug`
   --> $DIR/function-comparison-errors-59488.rs:31:5
    |
 LL |     assert_eq!(Foo::Bar, i);
    |     ^^^^^^^^^^^^^^^^^^^^^^^ the trait `Debug` is not implemented for fn item `fn(usize) -> Foo {Foo::Bar}`
-   |
-   = note: this error originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error[E0277]: `fn(usize) -> Foo {Foo::Bar}` doesn't implement `Debug`
   --> $DIR/function-comparison-errors-59488.rs:31:5
    |
 LL |     assert_eq!(Foo::Bar, i);
    |     ^^^^^^^^^^^^^^^^^^^^^^^ the trait `Debug` is not implemented for fn item `fn(usize) -> Foo {Foo::Bar}`
-   |
-   = note: this error originates in the macro `assert_eq` (in Nightly builds, run with -Z macro-backtrace for more info)
 
 error: aborting due to 10 previous errors