Port the without_debuginfo test from backtrace-rs to the testsuite

library/std/src/backtrace.rs

@@ -159,7 +159,10 @@ enum RawFrame {
     Fake,
 }
 
-struct BacktraceSymbol {
+/// A single symbol associated with a backtrace frame, which may include a
+/// function name, filename, line number, and column number.
+#[unstable(feature = "backtrace_internals_accessors", issue = "122899")]
+pub struct BacktraceSymbol {
     name: Option<Vec<u8>>,
     filename: Option<BytesOrWide>,
     lineno: Option<u32>,
@@ -207,6 +210,41 @@ impl fmt::Debug for BacktraceFrame {
     }
 }
 
+///NOTE: This is never intended to become stable. It doesn't have an ACP
+/// Its meant to help us port the tests mentioned in issue #122899
+#[unstable(feature = "backtrace_internals_accessors", issue = "122899")]
+impl BacktraceFrame {
+    /// Returns the instruction pointer associated with this frame.
+    pub fn ip(&self) -> *mut c_void {
+        self.frame.ip()
+    }
+
+    /// Returns the symbols associated with this frame, if any.
+    pub fn symbols(&self) -> &[BacktraceSymbol] {
+        &self.symbols
+    }
+
+    /// Returns the base address of the module this frame belongs to, if available.
+    pub fn module_base_address(&self) -> Option<*mut c_void> {
+        match &self.frame {
+            RawFrame::Actual(frame) => frame.module_base_address(),
+            #[cfg(test)]
+            RawFrame::Fake => None,
+        }
+    }
+}
+
+///NOTE: This is never intended to become stable. It doesn't have an ACP
+/// Its meant to help us port the tests mentioned in issue #122899
+impl BacktraceSymbol {
+    /// Returns the name of this symbol, if available.
+    #[unstable(feature = "backtrace_internals_accessors", issue = "122899")]
+    pub fn name(&self) -> Option<&[u8]> {
+        self.name.as_deref()
+    }
+}
+
+#[unstable(feature = "backtrace_internals_accessors", issue = "122899")]
 impl fmt::Debug for BacktraceSymbol {
     fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
         // FIXME: improve formatting: https://github.com/rust-lang/rust/issues/65280

tests/ui/README.md

@@ -1,12 +1,12 @@
 # UI Test Suite Categories
 
-This is a high-level summary of the organization of the UI test suite (`tests/ui/`). It is not intended to be *prescriptive*, but instead provide a quick survey of existing groupings.
+This is a high-level summary of the organization of the UI test suite (`tests/ui/`). It is not intended to be _prescriptive_, but instead provide a quick survey of existing groupings.
 
 For now, only immediate subdirectories under `tests/ui/` are described, but these subdirectories can themselves include a `SUMMARY.md` to further describe their own organization and intent, should that be helpful.
 
 ## `tests/ui/abi`
 
-These tests deal with *Application Binary Interfaces* (ABI), mostly relating to function name mangling (and the `#[no_mangle]` attribute), calling conventions, or compiler flags which affect ABI.
+These tests deal with _Application Binary Interfaces_ (ABI), mostly relating to function name mangling (and the `#[no_mangle]` attribute), calling conventions, or compiler flags which affect ABI.
 
 Tests for unsupported ABIs can be made cross-platform by using the `extern "rust-invalid"` ABI, which is considered unsupported on every platform.
 
@@ -198,13 +198,13 @@ See [Conditional compilation | Reference](https://doc.rust-lang.org/reference/co
 
 ## `tests/ui/check-cfg/`: Configuration Checks
 
-Tests for the `--check-cfg` compiler mechanism  for checking cfg configurations, for `#[cfg(..)]` and `cfg!(..)`.
+Tests for the `--check-cfg` compiler mechanism for checking cfg configurations, for `#[cfg(..)]` and `cfg!(..)`.
 
 See [Checking conditional configurations | The rustc book](https://doc.rust-lang.org/rustc/check-cfg.html).
 
 ## `tests/ui/closure-expected-type/`: Closure type inference
 
-Tests targeted at how we deduce the types of closure arguments. This process is a result of some heuristics which take into account the *expected type* we have alongside the *actual types* that we get from inputs.
+Tests targeted at how we deduce the types of closure arguments. This process is a result of some heuristics which take into account the _expected type_ we have alongside the _actual types_ that we get from inputs.
 
 **FIXME**: Appears to have significant overlap with `tests/ui/closure_context` and `tests/ui/functions-closures/closure-expected-type`. Needs further investigation.
 
@@ -272,7 +272,7 @@ This directory is actually for the standard library [`std::process::Command`](ht
 
 Some traits' implementation must be compared with their definition, checking for problems such as the implementation having stricter requirements (such as needing to implement `Copy`).
 
-This subdirectory is *not* intended comparison traits (`PartialEq`, `Eq`, `PartialOrd`, `Ord`).
+This subdirectory is _not_ intended comparison traits (`PartialEq`, `Eq`, `PartialOrd`, `Ord`).
 
 ## `tests/ui/compile-flags/`
 
@@ -885,7 +885,7 @@ Tests on [AST lowering](https://rustc-dev-guide.rust-lang.org/ast-lowering.html)
 
 ## `tests/ui/lto/`
 
-Exercise *Link-Time Optimization* (LTO), involving the flags `-C lto` or `-Z thinlto`.
+Exercise _Link-Time Optimization_ (LTO), involving the flags `-C lto` or `-Z thinlto`.
 
 ## `tests/ui/lub-glb/`: LUB/GLB algorithm update
 
@@ -973,6 +973,10 @@ See [RFC 3550 New Range](https://github.com/rust-lang/rfcs/blob/master/text/3550
 
 Tests for Non-lexical lifetimes. See [RFC 2094 NLL](https://rust-lang.github.io/rfcs/2094-nll.html).
 
+## `tests/ui/no_debuginfo`: without_debuginfo test ported from backtrace-rs
+
+Tests for behavior when debug information is not available, ported from `backtrace-rs`'s `without_debuginfo` crate's test.
+
 ## `tests/ui/no_std/`
 
 Tests for where the standard library is disabled through `#![no_std]`.
@@ -1368,7 +1372,7 @@ Generic collection of tests for suggestions, when no more specific directories a
 
 ## `tests/ui/svh/`: Strict Version Hash
 
-Tests on the *Strict Version Hash* (SVH, also known as the "crate hash").
+Tests on the _Strict Version Hash_ (SVH, also known as the "crate hash").
 
 See [Strict Version Hash](https://rustc-dev-guide.rust-lang.org/backend/libs-and-metadata.html#strict-version-hash).
 

tests/ui/no_debuginfo/all_frames_have_module_base_address.rs

@@ -0,0 +1,20 @@
+//@ compile-flags: -Cstrip=none -Cdebuginfo=none
+//@ run-pass
+#![feature(backtrace_frames)]
+#![feature(backtrace_internals_accessors)]
+use std::backtrace;
+
+fn main() {
+    let mut missing_base_addresses = 0;
+    let btrace = backtrace::Backtrace::force_capture();
+    let frames = btrace.frames();
+    for frame in frames {
+        if frame.module_base_address().is_none() {
+            missing_base_addresses += 1;
+        }
+    }
+
+    if cfg!(windows) {
+        assert_eq!(missing_base_addresses, 0);
+    }
+}

tests/ui/no_debuginfo/all_frames_have_symbols.rs

@@ -0,0 +1,33 @@
+//@ compile-flags: -Cstrip=none -Cdebuginfo=none
+//@ run-pass
+#![feature(backtrace_frames)]
+#![feature(backtrace_internals_accessors)]
+use std::backtrace;
+fn main() {
+    let mut missing_symbols = 0;
+    let mut has_symbols = 0;
+    let btrace = backtrace::Backtrace::force_capture();
+    let frames = btrace.frames();
+    for frame in frames {
+        let mut any = false;
+        for sym in frame.symbols() {
+            if sym.name().is_some() {
+                any = true;
+                break;
+            }
+        }
+        if any {
+            has_symbols += 1;
+        } else if !frame.ip().is_null() {
+            missing_symbols += 1;
+        }
+    }
+
+    // FIXME(#346) currently on MinGW we can't symbolize kernel32.dll and other
+    // system libraries, which means we miss the last few symbols.
+    if cfg!(windows) && cfg!(target_env = "gnu") {
+        assert!(missing_symbols < has_symbols && has_symbols > 4);
+    } else {
+        assert_eq!(missing_symbols, 0);
+    }
+}