bin: prefer symbol table names over DWARF names (#332)

Prefer the symbol table over the DWARF name because:
- the symbol can include a clone suffix
- llvm may omit the linkage name in the DWARF with -g1

These two cases are tested in testoutput/dwarf/cold
and testoutput/dwarf/base-clang-g1.

This also fixes the case where the DWARF includes an inlined
function with no name, and we wrongly used the symbol table.
I don't have a test case for this.

Author: philipc

Cargo.toml

@@ -59,7 +59,7 @@ codegen-units = 1
 default = ["rustc-demangle", "cpp_demangle", "loader", "fallible-iterator", "smallvec"]
 std = ["gimli/std"]
 loader = ["std", "dep:object", "dep:memmap2", "dep:typed-arena"]
-bin = ["loader", "rustc-demangle", "cpp_demangle", "smallvec", "dep:clap"]
+bin = ["loader", "rustc-demangle", "cpp_demangle", "fallible-iterator", "smallvec", "dep:clap"]
 all = ["bin"]
 
 # Use of --all-features is not supported.

src/bin/addr2line.rs

@@ -1,3 +1,4 @@
+use fallible_iterator::FallibleIterator;
 use std::borrow::Cow;
 use std::io::{BufRead, Lines, StdinLock, Write};
 use std::path::{Path, PathBuf};
@@ -210,7 +211,7 @@ fn main() {
         if opts.do_functions || opts.do_inlines {
             let mut printed_anything = false;
             if let Some(probe) = probe {
-                let mut frames = ctx.find_frames(probe).unwrap();
+                let mut frames = ctx.find_frames(probe).unwrap().peekable();
                 let mut first = true;
                 while let Some(frame) = frames.next().unwrap() {
                     if opts.pretty && !first {
@@ -219,15 +220,25 @@ fn main() {
                     first = false;
 
                     if opts.do_functions {
-                        if let Some(func) = frame.function {
+                        // Only use the symbol table if this isn't an inlined function.
+                        let symbol = if matches!(frames.peek(), Ok(None)) {
+                            ctx.find_symbol(probe)
+                        } else {
+                            None
+                        };
+                        if symbol.is_some() {
+                            // Prefer the symbol table over the DWARF name because:
+                            // - the symbol can include a clone suffix
+                            // - llvm may omit the linkage name in the DWARF with -g1
+                            print_function(symbol, None, opts.demangle);
+                        } else if let Some(func) = frame.function {
                             print_function(
                                 func.raw_name().ok().as_deref(),
                                 func.language,
                                 opts.demangle,
                             );
                         } else {
-                            let name = ctx.find_symbol(probe);
-                            print_function(name, None, opts.demangle);
+                            print_function(None, None, opts.demangle);
                         }
 
                         if opts.pretty {

testoutput/dwarf/base-clang-g1

@@ -11,39 +11,39 @@ _ZN3Foo3barEPKc
 _ZN3Foo3barEPKc
 /object/testfiles/dwarf/base.cpp:16
 0x00000000000011a0
-foo
+_ZN3Foo3fooEi
 /object/testfiles/dwarf/base.cpp:19
 0x00000000000011ac
-foo
+_ZN3Foo3fooEi
 /object/testfiles/dwarf/base.cpp:20
 0x00000000000011b0
-foo
+_ZN3Foo3fooEi
 /object/testfiles/dwarf/base.cpp:?
 0x00000000000011d0
 bar
 /object/testfiles/dwarf/base.cpp:15
-foo
+_ZN3Foo3fooEi
 /object/testfiles/dwarf/base.cpp:21
 0x000000000000120e
 bar
 /object/testfiles/dwarf/base.cpp:14
-foo
+_ZN3Foo3fooEi
 /object/testfiles/dwarf/base.cpp:21
 0x000000000000121c
-foo
+_ZN3Foo3fooEi
 /object/testfiles/dwarf/base.cpp:?
 0x0000000000001230
 bar
 /object/testfiles/dwarf/base.cpp:15
-foo
+_ZN3Foo3fooEi
 /object/testfiles/dwarf/base.cpp:23
 0x000000000000126e
 bar
 /object/testfiles/dwarf/base.cpp:14
-foo
+_ZN3Foo3fooEi
 /object/testfiles/dwarf/base.cpp:23
 0x000000000000127a
-foo
+_ZN3Foo3fooEi
 /object/testfiles/dwarf/base.cpp:24
 0x0000000000001280
 main

testoutput/dwarf/cold

@@ -1,31 +1,31 @@
 0x0000000000001060
-_ZN3Foo3fooEi
+_ZN3Foo3fooEi.cold
 /object/testfiles/dwarf/cold.cpp:29
 0x0000000000001067
-_ZN3Foo3fooEi
+_ZN3Foo3fooEi.cold
 /object/testfiles/dwarf/cold.cpp:29
 0x000000000000106e
 _ZN3Foo3barEPKc
 /object/testfiles/dwarf/cold.cpp:20
-_ZN3Foo3fooEi
+_ZN3Foo3fooEi.cold
 /object/testfiles/dwarf/cold.cpp:29
 0x0000000000001075
 _ZN3Foo3barEPKc
 /object/testfiles/dwarf/cold.cpp:21
-_ZN3Foo3fooEi
+_ZN3Foo3fooEi.cold
 /object/testfiles/dwarf/cold.cpp:29
 0x0000000000001078
 _ZN3Foo3barEPKc
 /object/testfiles/dwarf/cold.cpp:20
-_ZN3Foo3fooEi
+_ZN3Foo3fooEi.cold
 /object/testfiles/dwarf/cold.cpp:29
 0x000000000000107c
 _ZN3Foo3barEPKc
 /object/testfiles/dwarf/cold.cpp:20
-_ZN3Foo3fooEi
+_ZN3Foo3fooEi.cold
 /object/testfiles/dwarf/cold.cpp:29
 0x0000000000001081
-_ZN3Foo3fooEi
+_ZN3Foo3fooEi.cold
 /object/testfiles/dwarf/cold.cpp:30
 0x0000000000001082
 _ZN3Foo3barEPKc