Version 3.4.5

* Copy strings without escape sequences in them

* Add support for more encodings from encoding_rs

Also use encoding_rs instead of CStr for UTF-8.

Cargo.toml

@@ -14,7 +14,7 @@ default-members = [
 resolver = "3"
 
 [workspace.package]
-version = "3.3.0"
+version = "3.4.5"
 authors = ["Luke Street <luke@street.dev>"]
 edition = "2024"
 license = "MIT OR Apache-2.0"

deny.toml

@@ -75,6 +75,7 @@ ignore = [
     #{ crate = "a-crate-that-is-yanked@0.1.1", reason = "you can specify why you are ignoring the yanked crate" },
     { id = "RUSTSEC-2024-0436", reason = "Unmaintained paste crate is an indirect dependency" },
     { id = "RUSTSEC-2025-0052", reason = "Unmaintained async-std crate is an indirect dependency" },
+    { id = "RUSTSEC-2025-0119", reason = "Unmaintained number_prefix crate is an indirect dependency" },
 ]
 # If this is true, then cargo deny will use the git executable to fetch advisory database.
 # If this is false, then it uses a built-in git library.

objdiff-cli/Cargo.toml

@@ -16,19 +16,19 @@ publish = false
 anyhow = "1.0"
 argp = "0.4"
 crossterm = "0.29"
-enable-ansi-support = "0.2"
+enable-ansi-support = "0.3"
 memmap2 = "0.9"
 objdiff-core = { path = "../objdiff-core", features = ["all"] }
 prost = "0.14"
 ratatui = "0.29"
-rayon = "1.10"
+rayon = "1.11"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
 supports-color = "3.0"
 time = { version = "0.3", features = ["formatting", "local-offset"] }
 tracing = "0.1"
 tracing-subscriber = { version = "0.3", features = ["env-filter"] }
-typed-path = "0.11"
+typed-path = "0.12"
 
 [target.'cfg(target_env = "musl")'.dependencies]
 mimalloc = "0.1"

objdiff-cli/src/cmd/diff.rs

@@ -66,15 +66,6 @@ pub struct Args {
     #[argp(option, short = 'c')]
     /// Configuration property (key=value)
     config: Vec<String>,
-    #[argp(option, short = 'm')]
-    /// Symbol mapping (target=base)
-    mapping: Vec<String>,
-    #[argp(option)]
-    /// Left symbol name for selection
-    selecting_left: Option<String>,
-    #[argp(option)]
-    /// Right symbol name for selection
-    selecting_right: Option<String>,
 }
 
 pub fn run(args: Args) -> Result<()> {
@@ -183,17 +174,7 @@ fn build_config_from_args(
         apply_project_options(&mut diff_config, options)?;
     }
     apply_config_args(&mut diff_config, &args.config)?;
-    let mut mapping_config = MappingConfig {
-        mappings: Default::default(),
-        selecting_left: args.selecting_left.clone(),
-        selecting_right: args.selecting_right.clone(),
-    };
-    for mapping in &args.mapping {
-        let (target, base) =
-            mapping.split_once('=').context("--mapping expects \"target=base\"")?;
-        mapping_config.mappings.insert(target.to_string(), base.to_string());
-    }
-    Ok((diff_config, mapping_config))
+    Ok((diff_config, MappingConfig::default()))
 }
 
 pub struct AppState {

objdiff-cli/src/views/function_diff.rs

@@ -378,7 +378,6 @@ impl UiView for FunctionDiffUi {
                     }
                     // Reload
                     KeyCode::Char('r') => {
-                        result.redraw = true;
                         return EventControlFlow::Reload;
                     }
                     // Scroll right
@@ -400,7 +399,6 @@ impl UiView for FunctionDiffUi {
                                 FunctionRelocDiffs::DataValue => FunctionRelocDiffs::All,
                                 FunctionRelocDiffs::All => FunctionRelocDiffs::None,
                             };
-                        result.redraw = true;
                         return EventControlFlow::Reload;
                     }
                     // Toggle three-way diff

objdiff-core/Cargo.toml

@@ -132,13 +132,13 @@ itertools = { version = "0.14", default-features = false, features = ["use_alloc
 log = { version = "0.4", default-features = false, optional = true }
 memmap2 = { version = "0.9", optional = true }
 num-traits = { version = "0.2", default-features = false, optional = true }
-object = { git = "https://github.com/encounter/object", branch = "omf", default-features = false, features = ["read_core", "elf", "coff", "omf"] }
+object = { version = "0.37", default-features = false, features = ["read_core", "elf", "coff"] }
 pbjson = { version = "0.8", default-features = false, optional = true }
 prost = { version = "0.14", default-features = false, features = ["derive"], optional = true }
-regex = { version = "1.11", default-features = false, features = [], optional = true }
+regex = { version = "1.12", default-features = false, features = [], optional = true }
 serde = { version = "1.0", default-features = false, features = ["derive"], optional = true }
 similar = { git = "https://github.com/encounter/similar.git", branch = "no_std", default-features = false, features = ["hashbrown"], optional = true }
-typed-path = { version = "0.11", default-features = false, optional = true }
+typed-path = { version = "0.12", default-features = false, optional = true }
 
 # config
 globset = { version = "0.4", default-features = false, optional = true }
@@ -155,13 +155,13 @@ powerpc = { version = "0.4", optional = true }
 rlwinmdec = { version = "1.1", optional = true }
 
 # mips
-rabbitizer = { version = "2.0.0-alpha.4", default-features = false, features = ["all_extensions"], optional = true }
+rabbitizer = { version = "2.0.0-alpha.7", default-features = false, features = ["all_extensions"], optional = true }
 
 # x86
 iced-x86 = { version = "1.21", default-features = false, features = ["decoder", "intel", "gas", "masm", "nasm", "exhaustive_enums", "no_std"], optional = true }
 
 # arm
-unarm = { version = "1.9", optional = true }
+unarm = { version = "2.1", optional = true }
 arm-attr = { version = "0.2", optional = true }
 
 # arm64
@@ -169,17 +169,17 @@ yaxpeax-arch = { version = "0.3", default-features = false, optional = true }
 yaxpeax-arm = { version = "0.3", default-features = false, optional = true }
 
 # build
-notify = { version = "8.1.0", optional = true }
-notify-debouncer-full = { version = "0.5.0", optional = true }
+notify = { version = "8.2.0", optional = true }
+notify-debouncer-full = { version = "0.6.0", optional = true }
 shell-escape = { version = "0.1", optional = true }
-tempfile = { version = "3.20", optional = true }
+tempfile = { version = "3.23", optional = true }
 time = { version = "0.3", optional = true }
 encoding_rs = { version = "0.8.35", optional = true }
 
 # demangler
-cpp_demangle = { version = "0.4", optional = true, default-features = false, features = ["alloc"] }
+cpp_demangle = { version = "0.5", optional = true, default-features = false, features = ["alloc"] }
 cwdemangle = { version = "1.0", optional = true }
-gnuv2_demangle = { version = "0.1.0", optional = true }
+gnuv2_demangle = { version = "0.4", optional = true }
 msvc-demangler = { version = "0.11", optional = true }
 
 [target.'cfg(windows)'.dependencies]

objdiff-core/config-schema.json

@@ -82,6 +82,27 @@
       "name": "Space between args",
       "description": "Adds a space between arguments in the diff output."
     },
+    {
+      "id": "showSymbolSizes",
+      "type": "choice",
+      "default": "off",
+      "name": "Show symbol sizes",
+      "description": "Shows symbol sizes in the symbol view.",
+      "items": [
+        {
+          "value": "off",
+          "name": "Off"
+        },
+        {
+          "value": "hex",
+          "name": "Hex"
+        },
+        {
+          "value": "decimal",
+          "name": "Decimal"
+        }
+      ]
+    },
     {
       "id": "combineDataSections",
       "type": "boolean",
@@ -107,20 +128,43 @@
           "value": "auto",
           "name": "Auto"
         },
+        {
+          "value": "v4",
+          "name": "ARMv4"
+        },
         {
           "value": "v4t",
           "name": "ARMv4T (GBA)"
         },
+        {
+          "value": "v5t",
+          "name": "ARMv5T"
+        },
         {
           "value": "v5te",
           "name": "ARMv5TE (DS)"
         },
+        {
+          "value": "v5tej",
+          "name": "ARMv5TEJ"
+        },
+        {
+          "value": "v6",
+          "name": "ARMv6"
+        },
         {
           "value": "v6k",
           "name": "ARMv6K (3DS)"
         }
       ]
     },
+    {
+      "id": "arm.vfpV2",
+      "type": "boolean",
+      "default": true,
+      "name": "VFPv2 instructions",
+      "description": "Adds floating-point instructions from VFPv2."
+    },
     {
       "id": "arm.unifiedSyntax",
       "type": "boolean",
@@ -296,6 +340,7 @@
       "properties": [
         "functionRelocDiffs",
         "demangler",
+        "showSymbolSizes",
         "spaceBetweenArgs",
         "combineDataSections",
         "combineTextSections"
@@ -306,6 +351,7 @@
       "name": "ARM",
       "properties": [
         "arm.archVersion",
+        "arm.vfpV2",
         "arm.unifiedSyntax",
         "arm.avRegisters",
         "arm.r9Usage",

objdiff-core/src/arch/mips.rs

@@ -293,6 +293,7 @@ impl Arch for ArchMips {
                         }
                         elf::R_MIPS_PC16 => 0, // PC-relative relocation
                         R_MIPS15_S3 => ((code & 0x001FFFC0) >> 3) as i64,
+                        elf::R_MIPS_GPREL32 => (code as i32 as i64) + self.ri_gp_value as i64,
                         flags => bail!("Unsupported MIPS implicit relocation {flags:?}"),
                     };
                     Ok(Some(RelocationOverride { target: RelocationOverrideTarget::Keep, addend }))
@@ -318,6 +319,7 @@ impl Arch for ArchMips {
                 elf::R_MIPS_GOT16 => Some("R_MIPS_GOT16"),
                 elf::R_MIPS_PC16 => Some("R_MIPS_PC16"),
                 elf::R_MIPS_CALL16 => Some("R_MIPS_CALL16"),
+                elf::R_MIPS_GPREL32 => Some("R_MIPS_GPREL32"),
                 R_MIPS15_S3 => Some("R_MIPS15_S3"),
                 _ => None,
             },

objdiff-core/src/arch/mod.rs

@@ -7,12 +7,10 @@ use alloc::{
 };
 use core::{
     any::Any,
-    ffi::CStr,
     fmt::{self, Debug},
 };
 
 use anyhow::{Result, bail};
-use encoding_rs::SHIFT_JIS;
 use object::Endian as _;
 
 use crate::{
@@ -44,6 +42,16 @@ pub mod x86;
 pub const OPCODE_INVALID: u16 = u16::MAX;
 pub const OPCODE_DATA: u16 = u16::MAX - 1;
 
+const SUPPORTED_ENCODINGS: [(&encoding_rs::Encoding, &str); 7] = [
+    (encoding_rs::UTF_8, "UTF-8"),
+    (encoding_rs::SHIFT_JIS, "Shift JIS"),
+    (encoding_rs::UTF_16BE, "UTF-16BE"),
+    (encoding_rs::UTF_16LE, "UTF-16LE"),
+    (encoding_rs::WINDOWS_1252, "Windows-1252"),
+    (encoding_rs::EUC_JP, "EUC-JP"),
+    (encoding_rs::BIG5, "Big5"),
+];
+
 /// Represents the type of data associated with an instruction
 #[derive(PartialEq)]
 pub enum DataType {
@@ -77,7 +85,7 @@ impl DataType {
         let mut strs = Vec::new();
         for (literal, label_override) in self.display_literals(endian, bytes) {
             let label = label_override.unwrap_or_else(|| self.to_string());
-            strs.push(format!("{label}: {literal}"))
+            strs.push(format!("{label}: {literal:?}"))
         }
         strs
     }
@@ -164,16 +172,18 @@ impl DataType {
                 strs.push((format!("{bytes:#?}"), None));
             }
             DataType::String => {
-                if let Ok(cstr) = CStr::from_bytes_until_nul(bytes) {
-                    strs.push((format!("{cstr:?}"), None));
-                }
                 if let Some(nul_idx) = bytes.iter().position(|&c| c == b'\0') {
-                    let (cow, _, had_errors) = SHIFT_JIS.decode(&bytes[..nul_idx]);
-                    if !had_errors {
-                        let str = format!("{cow:?}");
-                        // Only add the Shift JIS string if it's different from the ASCII string.
-                        if !strs.iter().any(|x| x.0 == str) {
-                            strs.push((str, Some("Shift JIS".into())));
+                    let str_bytes = &bytes[..nul_idx];
+                    // Special case to display (ASCII) as the label for ASCII-only strings.
+                    let (cow, _, had_errors) = encoding_rs::UTF_8.decode(str_bytes);
+                    if !had_errors && cow.is_ascii() {
+                        strs.push((format!("{cow}"), Some("ASCII".into())));
+                    }
+                    for (encoding, encoding_name) in SUPPORTED_ENCODINGS {
+                        let (cow, _, had_errors) = encoding.decode(str_bytes);
+                        // Avoid showing ASCII-only strings more than once if the encoding is ASCII-compatible.
+                        if !had_errors && (!encoding.is_ascii_compatible() || !cow.is_ascii()) {
+                            strs.push((format!("{cow}"), Some(encoding_name.into())));
                         }
                     }
                 }

objdiff-core/src/arch/ppc/mod.rs

@@ -332,7 +332,6 @@ impl Arch for ArchPpc {
                 pe::IMAGE_REL_PPC_PAIR => Some("IMAGE_REL_PPC_PAIR"),
                 _ => None,
             },
-            _ => None,
         }
     }
 

objdiff-core/src/arch/x86.rs

@@ -72,7 +72,6 @@ impl ArchX86 {
                     elf::R_386_16 => Some(2),
                     _ => None,
                 },
-                RelocationFlags::Omf() => Some(4), // TODO
             },
             Architecture::X86_64 => match flags {
                 RelocationFlags::Coff(typ) => match typ {
@@ -85,7 +84,6 @@ impl ArchX86 {
                     elf::R_X86_64_64 => Some(8),
                     _ => None,
                 },
-                RelocationFlags::Omf() => None, // TODO
             },
         }
     }

objdiff-core/src/diff/data.rs

@@ -37,12 +37,13 @@ pub fn diff_bss_symbol(
 
 pub fn symbol_name_matches(left_name: &str, right_name: &str) -> bool {
     // Match Metrowerks symbol$1234 against symbol$2345
-    if let Some((prefix, suffix)) = left_name.split_once('$') {
+    // and GCC symbol.1234 against symbol.2345
+    if let Some((prefix, suffix)) = left_name.split_once(['$', '.']) {
         if !suffix.chars().all(char::is_numeric) {
             return false;
         }
         right_name
-            .split_once('$')
+            .split_once(['$', '.'])
             .is_some_and(|(p, s)| p == prefix && s.chars().all(char::is_numeric))
     } else {
         left_name == right_name
@@ -587,6 +588,7 @@ fn symbols_matching_section(
         s.section == Some(section_idx)
             && s.kind != SymbolKind::Section
             && s.size > 0
+            && !s.flags.contains(SymbolFlag::Hidden)
             && !s.flags.contains(SymbolFlag::Ignored)
     })
 }

objdiff-core/src/diff/demangler.rs

@@ -34,14 +34,12 @@ impl Demangler {
 
     fn demangle_itanium(name: &str) -> Option<String> {
         let name = name.trim_start_matches('.');
-        cpp_demangle::Symbol::new(name)
-            .ok()
-            .and_then(|s| s.demangle(&cpp_demangle::DemangleOptions::default()).ok())
+        cpp_demangle::Symbol::new(name).ok().and_then(|s| s.demangle().ok())
     }
 
     fn demangle_gnu_legacy(name: &str) -> Option<String> {
         let name = name.trim_start_matches('.');
-        gnuv2_demangle::demangle(name, &gnuv2_demangle::DemangleConfig::new_no_cfilt_mimics()).ok()
+        gnuv2_demangle::demangle(name, &gnuv2_demangle::DemangleConfig::new()).ok()
     }
 }
 

objdiff-core/src/diff/display.rs

@@ -668,7 +668,7 @@ pub fn instruction_hover(
                 for (literal, label_override) in literals {
                     out.push(HoverItem::Text {
                         label: label_override.unwrap_or_else(|| ty.to_string()),
-                        value: literal,
+                        value: format!("{literal:?}"),
                         color: HoverItemColor::Normal,
                     });
                 }

objdiff-core/src/obj/mdebug.rs

@@ -0,0 +1,401 @@
+use alloc::vec::Vec;
+
+use anyhow::{Context, Result, bail, ensure};
+use object::{Endianness, Object, ObjectSection};
+
+use super::{Section, SectionKind};
+
+const HDRR_SIZE: usize = 0x60;
+const FDR_SIZE: usize = 0x48;
+const PDR_SIZE: usize = 0x34;
+const SYMR_SIZE: usize = 0x0c;
+
+const ST_PROC: u8 = 6;
+const ST_STATICPROC: u8 = 14;
+const ST_END: u8 = 8;
+
+pub(super) fn parse_line_info_mdebug(
+    obj_file: &object::File,
+    sections: &mut [Section],
+) -> Result<()> {
+    let Some(section) = obj_file.section_by_name(".mdebug") else {
+        return Ok(());
+    };
+
+    let data = section.data().context("failed to read .mdebug contents")?;
+    if data.len() < HDRR_SIZE {
+        return Ok(());
+    }
+
+    let section_file_offset = section.file_range().map(|(offset, _)| offset as usize);
+
+    let endianness = obj_file.endianness();
+    let header = Header::parse(data, endianness)?;
+
+    let symbols_data = slice_at(
+        data,
+        header.cb_sym_offset,
+        header.isym_max.checked_mul(SYMR_SIZE as u32).context("symbol table size overflow")?,
+        section_file_offset,
+    )?;
+    let symbols = parse_symbols(symbols_data, endianness)?;
+
+    let fdr_data = slice_at(
+        data,
+        header.cb_fd_offset,
+        header
+            .ifd_max
+            .checked_mul(FDR_SIZE as u32)
+            .context("file descriptor table size overflow")?,
+        section_file_offset,
+    )?;
+
+    for fdr_index in 0..header.ifd_max as usize {
+        let fdr_offset = fdr_index * FDR_SIZE;
+        let fdr = FileDescriptor::parse(&fdr_data[fdr_offset..fdr_offset + FDR_SIZE], endianness)?;
+        if fdr.cpd == 0 || fdr.csym == 0 {
+            continue;
+        }
+
+        let sym_base = fdr.isym_base as usize;
+        let sym_end = sym_base + fdr.csym as usize;
+        if sym_end > symbols.len() {
+            continue;
+        }
+
+        let Some(line_file_offset) = header.cb_line_offset.checked_add(fdr.cb_line_offset) else {
+            continue;
+        };
+        let Some(line_file_base) =
+            resolve_offset(line_file_offset, data.len(), section_file_offset)
+        else {
+            continue;
+        };
+        let Some(line_file_end) = line_file_base.checked_add(fdr.cb_line as usize) else {
+            continue;
+        };
+        if line_file_end > data.len() {
+            continue;
+        }
+
+        for local_proc_index in 0..fdr.cpd as usize {
+            let pdr_index = fdr.ipd_first as usize + local_proc_index;
+            let pdr_offset = header
+                .cb_pd_offset
+                .checked_add((pdr_index as u32) * PDR_SIZE as u32)
+                .context("procedure descriptor offset overflow")?;
+            let pdr_data = match slice_at(data, pdr_offset, PDR_SIZE as u32, section_file_offset) {
+                Ok(data) => data,
+                Err(_) => continue,
+            };
+            let pdr = ProcDescriptor::parse(pdr_data, endianness)?;
+            if pdr.isym as usize >= fdr.csym as usize {
+                continue;
+            }
+            let global_sym_index = sym_base + pdr.isym as usize;
+            let Some(start_symbol) = symbols.get(global_sym_index) else {
+                continue;
+            };
+            if start_symbol.st != ST_PROC && start_symbol.st != ST_STATICPROC {
+                continue;
+            }
+
+            let local_index = pdr.isym as u32;
+            let mut end_address = None;
+            for sym in &symbols[global_sym_index..sym_end] {
+                if sym.st == ST_END && sym.index == local_index {
+                    end_address = Some(sym.value);
+                    break;
+                }
+            }
+            let Some(end_address) = end_address else {
+                continue;
+            };
+            let Some(size) = end_address.checked_sub(start_symbol.value) else {
+                continue;
+            };
+            if size == 0 || size % 4 != 0 {
+                continue;
+            }
+            let word_count = (size / 4) as usize;
+            if word_count == 0 {
+                continue;
+            }
+
+            let Some(mut cursor) = line_file_base.checked_add(pdr.cb_line_offset as usize) else {
+                continue;
+            };
+            if cursor >= line_file_end {
+                continue;
+            }
+
+            let mut line_number = pdr.ln_low as i32;
+            let mut lines = Vec::with_capacity(word_count);
+            while lines.len() < word_count && cursor < line_file_end {
+                let b0 = data[cursor];
+                cursor += 1;
+                let count = (b0 & 0x0f) as usize + 1;
+                let delta = decode_delta(endianness, b0 >> 4, data, &mut cursor, line_file_end)?;
+                line_number = line_number.wrapping_add(delta as i32);
+                for _ in 0..count {
+                    if lines.len() == word_count {
+                        break;
+                    }
+                    lines.push(line_number);
+                }
+            }
+
+            if lines.len() != word_count {
+                continue;
+            }
+
+            assign_lines(sections, fdr.adr as u64 + pdr.addr as u64, &lines);
+        }
+    }
+
+    Ok(())
+}
+
+fn assign_lines(sections: &mut [Section], base_address: u64, lines: &[i32]) {
+    let mut address = base_address;
+    for &line in lines {
+        if line >= 0
+            && let Some(section) = find_code_section(sections, address)
+        {
+            section.line_info.insert(address, line as u32);
+        }
+        address = address.wrapping_add(4);
+    }
+}
+
+fn find_code_section(sections: &mut [Section], address: u64) -> Option<&mut Section> {
+    sections.iter_mut().find(|section| {
+        section.kind == SectionKind::Code
+            && address >= section.address
+            && address < section.address + section.size
+    })
+}
+
+fn decode_delta(
+    endianness: Endianness,
+    nibble: u8,
+    data: &[u8],
+    cursor: &mut usize,
+    end: usize,
+) -> Result<i32> {
+    if nibble == 8 {
+        ensure!(*cursor + 2 <= end, "extended delta out of range");
+        let bytes: [u8; 2] = data[*cursor..*cursor + 2].try_into().unwrap();
+        *cursor += 2;
+        Ok(match endianness {
+            Endianness::Big => i16::from_be_bytes(bytes) as i32,
+            Endianness::Little => i16::from_le_bytes(bytes) as i32,
+        })
+    } else {
+        let mut value = (nibble & 0x0f) as i32;
+        if value & 0x8 != 0 {
+            value -= 0x10;
+        }
+        Ok(value)
+    }
+}
+
+fn slice_at(
+    data: &[u8],
+    offset: u32,
+    size: u32,
+    section_file_offset: Option<usize>,
+) -> Result<&[u8]> {
+    let size = size as usize;
+    if size == 0 {
+        ensure!(
+            resolve_offset(offset, data.len(), section_file_offset).is_some(),
+            "offset outside of .mdebug section"
+        );
+        return Ok(&data[0..0]);
+    }
+    let Some(offset) = resolve_offset(offset, data.len(), section_file_offset) else {
+        bail!("offset outside of .mdebug section");
+    };
+    let end = offset.checked_add(size).context("range overflow")?;
+    ensure!(end <= data.len(), "range exceeds .mdebug size");
+    Ok(&data[offset..end])
+}
+
+fn resolve_offset(
+    offset: u32,
+    data_len: usize,
+    section_file_offset: Option<usize>,
+) -> Option<usize> {
+    let offset = offset as usize;
+    if offset <= data_len {
+        Some(offset)
+    } else if let Some(file_offset) = section_file_offset {
+        offset.checked_sub(file_offset).filter(|rel| *rel <= data_len)
+    } else {
+        None
+    }
+}
+
+#[derive(Clone, Copy)]
+struct Header {
+    cb_line_offset: u32,
+    cb_pd_offset: u32,
+    cb_sym_offset: u32,
+    cb_fd_offset: u32,
+    isym_max: u32,
+    ifd_max: u32,
+}
+
+impl Header {
+    fn parse(data: &[u8], endianness: Endianness) -> Result<Self> {
+        ensure!(HDRR_SIZE <= data.len(), ".mdebug header truncated");
+        let mut cursor = 0;
+        let magic = read_u16(data, &mut cursor, endianness)?;
+        let _vstamp = read_u16(data, &mut cursor, endianness)?;
+        ensure!(magic == 0x7009, "unexpected .mdebug magic: {magic:#x}");
+        let _iline_max = read_u32(data, &mut cursor, endianness)?;
+        let _cb_line = read_u32(data, &mut cursor, endianness)?;
+        let cb_line_offset = read_u32(data, &mut cursor, endianness)?;
+        let _idn_max = read_u32(data, &mut cursor, endianness)?;
+        let _cb_dn_offset = read_u32(data, &mut cursor, endianness)?;
+        let _ipd_max = read_u32(data, &mut cursor, endianness)?;
+        let cb_pd_offset = read_u32(data, &mut cursor, endianness)?;
+        let isym_max = read_u32(data, &mut cursor, endianness)?;
+        let cb_sym_offset = read_u32(data, &mut cursor, endianness)?;
+        let _iopt_max = read_u32(data, &mut cursor, endianness)?;
+        let _cb_opt_offset = read_u32(data, &mut cursor, endianness)?;
+        let _iaux_max = read_u32(data, &mut cursor, endianness)?;
+        let _cb_aux_offset = read_u32(data, &mut cursor, endianness)?;
+        let _iss_max = read_u32(data, &mut cursor, endianness)?;
+        let _cb_ss_offset = read_u32(data, &mut cursor, endianness)?;
+        let _iss_ext_max = read_u32(data, &mut cursor, endianness)?;
+        let _cb_ss_ext_offset = read_u32(data, &mut cursor, endianness)?;
+        let ifd_max = read_u32(data, &mut cursor, endianness)?;
+        let cb_fd_offset = read_u32(data, &mut cursor, endianness)?;
+        let _crfd = read_u32(data, &mut cursor, endianness)?;
+        let _cb_rfd_offset = read_u32(data, &mut cursor, endianness)?;
+        let _iext_max = read_u32(data, &mut cursor, endianness)?;
+        let _cb_ext_offset = read_u32(data, &mut cursor, endianness)?;
+
+        Ok(Header { cb_line_offset, cb_pd_offset, cb_sym_offset, cb_fd_offset, isym_max, ifd_max })
+    }
+}
+
+#[derive(Clone, Copy)]
+struct FileDescriptor {
+    adr: u32,
+    isym_base: u32,
+    csym: u32,
+    ipd_first: u16,
+    cpd: u16,
+    cb_line_offset: u32,
+    cb_line: u32,
+}
+
+impl FileDescriptor {
+    fn parse(data: &[u8], endianness: Endianness) -> Result<Self> {
+        ensure!(data.len() >= FDR_SIZE, "FDR truncated");
+        let mut cursor = 0;
+        let adr = read_u32(data, &mut cursor, endianness)?;
+        let _rss = read_u32(data, &mut cursor, endianness)?;
+        let _iss_base = read_u32(data, &mut cursor, endianness)?;
+        let _cb_ss = read_u32(data, &mut cursor, endianness)?;
+        let isym_base = read_u32(data, &mut cursor, endianness)?;
+        let csym = read_u32(data, &mut cursor, endianness)?;
+        let _iline_base = read_u32(data, &mut cursor, endianness)?;
+        let _cline = read_u32(data, &mut cursor, endianness)?;
+        let _iopt_base = read_u32(data, &mut cursor, endianness)?;
+        let _copt = read_u32(data, &mut cursor, endianness)?;
+        let ipd_first = read_u16(data, &mut cursor, endianness)?;
+        let cpd = read_u16(data, &mut cursor, endianness)?;
+        let _iaux_base = read_u32(data, &mut cursor, endianness)?;
+        let _caux = read_u32(data, &mut cursor, endianness)?;
+        let _rfd_base = read_u32(data, &mut cursor, endianness)?;
+        let _crfd = read_u32(data, &mut cursor, endianness)?;
+        let _bits = read_u32(data, &mut cursor, endianness)?;
+        let cb_line_offset = read_u32(data, &mut cursor, endianness)?;
+        let cb_line = read_u32(data, &mut cursor, endianness)?;
+
+        Ok(FileDescriptor { adr, isym_base, csym, ipd_first, cpd, cb_line_offset, cb_line })
+    }
+}
+
+#[derive(Clone, Copy)]
+struct ProcDescriptor {
+    addr: u32,
+    isym: u32,
+    ln_low: i32,
+    cb_line_offset: u32,
+}
+
+impl ProcDescriptor {
+    fn parse(data: &[u8], endianness: Endianness) -> Result<Self> {
+        ensure!(data.len() >= PDR_SIZE, "PDR truncated");
+        let mut cursor = 0;
+        let addr = read_u32(data, &mut cursor, endianness)?;
+        let isym = read_u32(data, &mut cursor, endianness)?;
+        let _iline = read_u32(data, &mut cursor, endianness)?;
+        let _regmask = read_u32(data, &mut cursor, endianness)?;
+        let _regoffset = read_u32(data, &mut cursor, endianness)?;
+        let _iopt = read_u32(data, &mut cursor, endianness)?;
+        let _fregmask = read_u32(data, &mut cursor, endianness)?;
+        let _fregoffset = read_u32(data, &mut cursor, endianness)?;
+        let _frameoffset = read_u32(data, &mut cursor, endianness)?;
+        let _framereg = read_u16(data, &mut cursor, endianness)?;
+        let _pcreg = read_u16(data, &mut cursor, endianness)?;
+        let ln_low = read_i32(data, &mut cursor, endianness)?;
+        let _ln_high = read_i32(data, &mut cursor, endianness)?;
+        let cb_line_offset = read_u32(data, &mut cursor, endianness)?;
+
+        Ok(ProcDescriptor { addr, isym, ln_low, cb_line_offset })
+    }
+}
+
+#[derive(Clone, Copy)]
+struct SymbolEntry {
+    value: u32,
+    st: u8,
+    index: u32,
+}
+
+fn parse_symbols(data: &[u8], endianness: Endianness) -> Result<Vec<SymbolEntry>> {
+    ensure!(data.len().is_multiple_of(SYMR_SIZE), "symbol table misaligned");
+    let mut symbols = Vec::with_capacity(data.len() / SYMR_SIZE);
+    let mut cursor = 0;
+    while cursor + SYMR_SIZE <= data.len() {
+        let _iss = read_u32(data, &mut cursor, endianness)?;
+        let value = read_u32(data, &mut cursor, endianness)?;
+        let bits = read_u32(data, &mut cursor, endianness)?;
+        let (st, index) = match endianness {
+            Endianness::Big => (((bits >> 26) & 0x3f) as u8, bits & 0x000f_ffff),
+            Endianness::Little => (((bits & 0x3f) as u8), (bits >> 12) & 0x000f_ffff),
+        };
+        symbols.push(SymbolEntry { value, st, index });
+    }
+    Ok(symbols)
+}
+
+fn read_u16(data: &[u8], cursor: &mut usize, endianness: Endianness) -> Result<u16> {
+    ensure!(*cursor + 2 <= data.len(), "unexpected EOF while reading u16");
+    let bytes: [u8; 2] = data[*cursor..*cursor + 2].try_into().unwrap();
+    *cursor += 2;
+    Ok(match endianness {
+        Endianness::Big => u16::from_be_bytes(bytes),
+        Endianness::Little => u16::from_le_bytes(bytes),
+    })
+}
+
+fn read_u32(data: &[u8], cursor: &mut usize, endianness: Endianness) -> Result<u32> {
+    ensure!(*cursor + 4 <= data.len(), "unexpected EOF while reading u32");
+    let bytes: [u8; 4] = data[*cursor..*cursor + 4].try_into().unwrap();
+    *cursor += 4;
+    Ok(match endianness {
+        Endianness::Big => u32::from_be_bytes(bytes),
+        Endianness::Little => u32::from_le_bytes(bytes),
+    })
+}
+
+fn read_i32(data: &[u8], cursor: &mut usize, endianness: Endianness) -> Result<i32> {
+    Ok(read_u32(data, cursor, endianness)? as i32)
+}

objdiff-core/src/obj/mod.rs

@@ -1,5 +1,6 @@
 #[cfg(feature = "dwarf")]
 mod dwarf2;
+mod mdebug;
 pub mod read;
 pub mod split_meta;
 
@@ -370,7 +371,6 @@ pub struct Relocation {
 pub enum RelocationFlags {
     Elf(u32),
     Coff(u16),
-    Omf(/* TODO */),
 }
 
 #[derive(Debug, Copy, Clone)]

objdiff-core/src/obj/read.rs

@@ -510,7 +510,6 @@ fn map_section_relocations(
         let flags = match reloc.flags() {
             object::RelocationFlags::Elf { r_type } => RelocationFlags::Elf(r_type),
             object::RelocationFlags::Coff { typ } => RelocationFlags::Coff(typ),
-            object::RelocationFlags::Omf { .. } => RelocationFlags::Omf(/* TODO */),
             flags => bail!("Unhandled relocation flags: {:?}", flags),
         };
         let target_symbol = match symbol_indices.get(symbol_index.0).copied() {
@@ -655,6 +654,10 @@ fn parse_line_info(
         log::warn!("Failed to parse COFF line info: {e}");
     }
 
+    if let Err(e) = super::mdebug::parse_line_info_mdebug(obj_file, sections) {
+        log::warn!("Failed to parse MIPS mdebug line info: {e}");
+    }
+
     Ok(())
 }
 

objdiff-core/tests/arch_mips.rs

@@ -62,3 +62,21 @@ fn filter_non_matching() {
     .unwrap();
     insta::assert_debug_snapshot!(obj.symbols);
 }
+
+#[test]
+#[cfg(feature = "mips")]
+fn ido_mdebug_line_numbers() {
+    let diff_config = diff::DiffObjConfig::default();
+    let obj = obj::read::parse(
+        include_object!("data/mips/ido_lines_example.o"),
+        &diff_config,
+        diff::DiffSide::Base,
+    )
+    .unwrap();
+
+    let text_section = obj.sections.iter().find(|s| s.name == ".text").unwrap();
+    assert_eq!(text_section.line_info.get(&0), Some(&6));
+    assert_eq!(text_section.line_info.get(&12), Some(&7));
+    assert_eq!(text_section.line_info.get(&56), Some(&9));
+    assert_eq!(text_section.line_info.len(), 66);
+}