omit count

Author: chenyukang

library/std/src/sys_common/backtrace.rs

@@ -59,6 +59,7 @@ unsafe fn _print_fmt(fmt: &mut fmt::Formatter<'_>, print_fmt: PrintFmt) -> fmt::
     let mut bt_fmt = BacktraceFmt::new(fmt, print_fmt, &mut print_path);
     bt_fmt.add_context()?;
     let mut idx = 0;
+    let mut emitted_count: usize = 0;
     let mut res = Ok(());
     // Start immediately if we're not using a short backtrace.
     let mut start = print_fmt != PrintFmt::Short;
@@ -85,10 +86,17 @@ unsafe fn _print_fmt(fmt: &mut fmt::Formatter<'_>, print_fmt: PrintFmt) -> fmt::
                         start = true;
                         return;
                     }
+                    if !start {
+                        emitted_count += 1;
+                    }
                 }
             }
 
             if start {
+                if emitted_count > 0 {
+                    let _ = bt_fmt.print_omitted_count(emitted_count);
+                    emitted_count = 0;
+                }
                 res = bt_fmt.frame().symbol(frame, symbol);
             }
         });

tests/ui/consts/const-eval/const-eval-query-stack.stderr

@@ -1,5 +1,5 @@
 error[E0080]: evaluation of constant value failed
-  --> $DIR/const-eval-query-stack.rs:16:16
+  --> $DIR/const-eval-query-stack.rs:17:16
    |
 LL | const X: i32 = 1 / 0;
    |                ^^^^^ attempt to divide `1_i32` by zero

tests/ui/panics/short-ice-remove-middle-frames-2.rs

@@ -0,0 +1,60 @@
+// compile-flags:-Cstrip=none
+// run-fail
+// check-run-results
+// exec-env:RUST_BACKTRACE=1
+// ignore-android FIXME #17520
+// ignore-wasm no panic support
+// ignore-openbsd no support for libbacktrace without filename
+// ignore-emscripten no panic or subprocess support
+// ignore-sgx no subprocess support
+// ignore-fuchsia Backtraces not symbolized
+// ignore-msvc the `__rust_{begin,end}_short_backtrace` symbols aren't reliable.
+
+
+#[inline(never)]
+fn __rust_begin_short_backtrace<T, F: FnOnce() -> T>(f: F) -> T {
+    let result = f();
+    std::hint::black_box(result)
+}
+
+#[inline(never)]
+fn __rust_end_short_backtrace<T, F: FnOnce() -> T>(f: F) -> T {
+    let result = f();
+    std::hint::black_box(result)
+}
+
+fn first() {
+    __rust_end_short_backtrace(|| second());
+}
+
+fn second() {
+    third(); // won't show up
+}
+
+fn third() {
+    fourth(); // won't show up
+}
+
+fn fourth() {
+    __rust_begin_short_backtrace(|| fifth());
+}
+
+fn fifth() {
+    __rust_end_short_backtrace(|| sixth());
+}
+
+fn sixth() {
+    seven(); // won't show up
+}
+
+fn seven() {
+    __rust_begin_short_backtrace(|| eight());
+}
+
+fn eight() {
+    panic!("debug!!!");
+}
+
+fn main() {
+    first();
+}

tests/ui/panics/short-ice-remove-middle-frames-2.run.stderr

@@ -0,0 +1,13 @@
+thread 'main' panicked at 'debug!!!', $DIR/short-ice-remove-middle-frames-2.rs:55:5
+stack backtrace:
+   0: std::panicking::begin_panic
+   1: short_ice_remove_middle_frames_2::eight
+   2: short_ice_remove_middle_frames_2::seven::{{closure}}
+      ... omitted 3 frames ...
+   3: short_ice_remove_middle_frames_2::fifth
+   4: short_ice_remove_middle_frames_2::fourth::{{closure}}
+      ... omitted 4 frames ...
+   5: short_ice_remove_middle_frames_2::first
+   6: short_ice_remove_middle_frames_2::main
+   7: core::ops::function::FnOnce::call_once
+note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

tests/ui/panics/short-ice-remove-middle-frames.rs

@@ -5,8 +5,8 @@
 // ignore-android FIXME #17520
 // ignore-wasm no panic support
 // ignore-openbsd no support for libbacktrace without filename
-// ignore-emscripten no panic or subprocess support
-// ignore-sgx no subprocess support
+// ignore-emscripten no panic
+// ignore-sgx Backtraces not symbolized
 // ignore-fuchsia Backtraces not symbolized
 // ignore-msvc the `__rust_{begin,end}_short_backtrace` symbols aren't reliable.
 

tests/ui/panics/short-ice-remove-middle-frames.run.stderr

@@ -4,6 +4,7 @@ stack backtrace:
    1: short_ice_remove_middle_frames::seven
    2: short_ice_remove_middle_frames::sixth
    3: short_ice_remove_middle_frames::fifth::{{closure}}
+      ... omitted 4 frames ...
    4: short_ice_remove_middle_frames::second
    5: short_ice_remove_middle_frames::first::{{closure}}
    6: short_ice_remove_middle_frames::first