Commit d44db8ea0c35122aefbb1d86bed820b382eec988 | zig

author	Jacob Young <jacobly@ziglang.org> 2026-09-03 15:28:19-04:00
committer	Jacob Young <jacobly@ziglang.org> 2026-09-03 15:29:46-04:00
log	d44db8ea0c35122aefbb1d86bed820b382eec988
tree	0fea7dd49e2c56cb3410b6d6b9f675eb504f9aa8
parent	980bf80036a896ff01e7395c3887858ebae3e7f7

debug: fix and test Elf2 stack trace printing

- fix corrupt debug info
- fix dwarf unit version handling
- run stack and error trace tests with Elf2

5 files changed, 84 insertions(+), 42 deletions(-)

lib
- std
  - debug
    Dwarf.zig
src
- link
  - Dwarf2.zig
  - Elf2.zig
test
- src
  - ErrorTrace.zig
  - StackTrace.zig

lib/std/debug/Dwarf.zig+10-8

 @@ -387,18 +387,19 @@ fn scanAllFunctions(di: *Dwarf, gpa: Allocator, endian: Endian) ScanError!void {
         const next_offset = unit_header.header_length + unit_header.unit_length;
         const version = try fr.takeInt(u16, endian);
-        if (version < 2 or version > 5) return bad();
         var address_size: u8 = undefined;
         var debug_abbrev_offset: u64 = undefined;
-        if (version >= 5) {
+        if (version == 5) {
             const unit_type = try fr.takeByte();
             if (unit_type != DW.UT.compile) return bad();
             address_size = try fr.takeByte();
             debug_abbrev_offset = try readFormatSizedInt(&fr, unit_header.format, endian);
-        } else {
+        } else if (version >= 2 and version < 5) {
             debug_abbrev_offset = try readFormatSizedInt(&fr, unit_header.format, endian);
             address_size = try fr.takeByte();
+        } else {
+            this_unit_offset += next_offset;
+            continue;
         }
         const abbrev_table = try di.getAbbrevTable(gpa, debug_abbrev_offset);
 @@ -585,18 +586,19 @@ fn scanAllCompileUnits(di: *Dwarf, gpa: Allocator, endian: Endian) ScanError!voi
         const next_offset = unit_header.header_length + unit_header.unit_length;
         const version = try fr.takeInt(u16, endian);
-        if (version < 2 or version > 5) return bad();
         var address_size: u8 = undefined;
         var debug_abbrev_offset: u64 = undefined;
-        if (version >= 5) {
+        if (version == 5) {
             const unit_type = try fr.takeByte();
             if (unit_type != UT.compile) return bad();
             address_size = try fr.takeByte();
             debug_abbrev_offset = try readFormatSizedInt(&fr, unit_header.format, endian);
-        } else {
+        } else if (version >= 2 and version < 5) {
             debug_abbrev_offset = try readFormatSizedInt(&fr, unit_header.format, endian);
             address_size = try fr.takeByte();
+        } else {
+            this_unit_offset += next_offset;
+            continue;
         }
         const abbrev_table = try di.getAbbrevTable(gpa, debug_abbrev_offset);

src/link/Dwarf2.zig-6

 @@ -1058,7 +1058,6 @@ pub const WipNav = struct {
                 0
             else
                 zcu.navSrcLine(zcu.funcInfo(debug.wip_nav.func).owner_nav) + 1) + line);
-            try di_w.writeUleb128(line);
             try di_w.writeUleb128(column + 1);
             block.low_pc_off = code_off;
             try dwarf.addrSym(di_nw, debug.wip_nav.func_si, code_off);
 @@ -2898,11 +2897,6 @@ fn updateConstInner(
         else => return,
         .func => |func| {
-            const fi = try dwarf.getFunc(func.owner_nav);
-            switch (fi.get(dwarf).state) {
-                .unresolved => {},
-                .resolved => return,
-            }
             const fn_ty = ip.indexToKey(func.ty).func_type;
             const nav = ip.getNav(func.owner_nav);
             const inst_info = nav.srcInst(ip).resolveFull(ip).?;

src/link/Elf2.zig+19-21

 @@ -8753,7 +8753,7 @@ pub fn updateConst(
 ) link.Error!void {
     switch (val) {
         .anyerror_type => {}, // handled in `updateErrorData` instead
-        else => try elf.updateConstInner(pt, cpi, val),
+        else => try elf.updateConstInner(pt, cpi, val, .complete),
     }
 }
 fn updateConstInner(
 @@ -8761,11 +8761,22 @@ fn updateConstInner(
     pt: Zcu.PerThread,
     cpi: link.ConstPool.Index,
     val: InternPool.Index,
+    complete: enum { incomplete, complete },
 ) link.Error!void {
     switch (elf.base.comp.config.debug_format) {
         .strip => {},
         .dwarf => {
             {
+                switch (pt.zcu.intern_pool.indexToKey(val)) {
+                    else => {},
+                    .func => |func| {
+                        const fi = try elf.dwarf.getFunc(func.owner_nav);
+                        switch (fi.get(&elf.dwarf).state) {
+                            .unresolved => {},
+                            .resolved => return,
+                        }
+                    },
+                }
                 const gpa = elf.base.comp.gpa;
                 const debug_info_ni = Dwarf.Const.get(cpi, &elf.dwarf).debug_info_ni.unwrap().?;
                 try debug_info_ni.moved(gpa, &elf.mf);
 @@ -8773,7 +8784,10 @@ fn updateConstInner(
                 debug_info_ni.writer(gpa, &elf.mf, &di_nw);
                 defer di_nw.deinit();
                 elf.resetNodeRelocs(debug_info_ni);
-                try elf.dwarf.updateConst(pt, &di_nw, val);
+                switch (complete) {
+                    .incomplete => try elf.dwarf.updateConstIncomplete(pt, &di_nw, val),
+                    .complete => try elf.dwarf.updateConst(pt, &di_nw, val),
+                }
             }
             try elf.genPending(pt);
         },
 @@ -8787,23 +8801,7 @@ pub fn updateConstIncomplete(
     cpi: link.ConstPool.Index,
     val: InternPool.Index,
 ) link.Error!void {
-    switch (elf.base.comp.config.debug_format) {
+    return elf.updateConstInner(pt, cpi, val, .incomplete);
-        .strip => {},
-        .dwarf => {
-            {
-                const gpa = elf.base.comp.gpa;
-                const debug_info_ni = Dwarf.Const.get(cpi, &elf.dwarf).debug_info_ni.unwrap().?;
-                try debug_info_ni.moved(gpa, &elf.mf);
-                var di_nw: MappedFile.Node.Writer = undefined;
-                debug_info_ni.writer(gpa, &elf.mf, &di_nw);
-                defer di_nw.deinit();
-                elf.resetNodeRelocs(debug_info_ni);
-                try elf.dwarf.updateConstIncomplete(pt, &di_nw, val);
-            }
-            try elf.genPending(pt);
-        },
-        .code_view => unreachable,
-    }
 }
 pub fn updateFunc(
 @@ -9032,7 +9030,7 @@ fn updateFuncInner(
                 if (func.analysisUnordered(ip).inferred_error_set) {
                     const ies = ip.getIfExists(.{ .inferred_error_set_type = func_index }).?;
                     if (elf.dwarf.const_pool.getIfExists(ies)) |cpi|
-                        try elf.updateConstInner(pt, cpi, ies);
+                        try elf.updateConstInner(pt, cpi, ies, .complete);
                 }
             },
             .none => {},
 @@ -9083,7 +9081,7 @@ pub fn updateErrorData(elf: *Elf, pt: Zcu.PerThread) link.Error!void {
         .index = @intCast(lmi),
     });
     if (elf.dwarf.const_pool.getIfExists(.anyerror_type)) |cpi|
-        try elf.updateConstInner(pt, cpi, .anyerror_type);
+        try elf.updateConstInner(pt, cpi, .anyerror_type, .complete);
 }
 pub fn flush(

test/src/ErrorTrace.zig+29-5

 @@ -36,6 +36,7 @@ pub const CaseParameters = struct {
     optimize: OptimizeMode = .debug,
     use_llvm: ?bool = null,
     use_lld: ?bool = null,
+    use_new_linker: ?bool = null,
     // This is intended for targets that, for any reason, shouldn't be run as part of a normal test
     // invocation. This could be because of a slow backend, requiring a newer LLVM version, being
 @@ -256,6 +257,14 @@ pub const param_sets = [_]CaseParameters{
             .abi = .none,
         },
     },
+    .{
+        .target = .{
+            .cpu_arch = .x86_64,
+            .os_tag = .linux,
+            .abi = .none,
+        },
+        .use_new_linker = true,
+    },
     .{
         .target = .{
             .cpu_arch = .x86_64,
 @@ -265,6 +274,15 @@ pub const param_sets = [_]CaseParameters{
         .use_llvm = true,
         .use_lld = true,
     },
+    .{
+        .target = .{
+            .cpu_arch = .x86_64,
+            .os_tag = .linux,
+            .abi = .none,
+        },
+        .use_llvm = true,
+        .use_new_linker = true,
+    },
     .{
         .target = .{
             .cpu_arch = .x86_64,
 @@ -439,18 +457,23 @@ pub fn addCase(self: *ErrorTrace, case: Case) void {
     };
     const backend_string = if (params.use_llvm == true)
-        "-llvm"
+        " llvm"
     else if (params.use_llvm == false)
-        "-selfhosted"
+        " selfhosted"
     else
         "";
-    const annotated_case_name = b.fmt("check {s} ({s}{s}{t}{s})", .{
+    const annotated_case_name = b.fmt("check {s} ({s} {t}{s}{s})", .{
         case.name,
-        triple orelse "",
+        triple orelse "native",
-        if (triple != null) " " else "",
         params.optimize,
         backend_string,
+        if (params.use_new_linker == true)
+            " new_linker"
+        else if (params.use_lld == true)
+            " lld"
+        else
+            "",
     });
     if (self.options.test_filters.len > 0) {
         for (self.options.test_filters) |test_filter| {
 @@ -472,6 +495,7 @@ pub fn addCase(self: *ErrorTrace, case: Case) void {
         .use_llvm = params.use_llvm,
         .use_lld = params.use_lld,
     });
+    exe.use_new_linker = params.use_new_linker;
     exe.bundle_ubsan_rt = false;
     const run = b.addRunArtifact(exe);

test/src/StackTrace.zig+26-2

 @@ -38,6 +38,7 @@ pub const CaseParameters = struct {
     link_libc: ?bool = null,
     use_llvm: ?bool = null,
     use_lld: ?bool = null,
+    use_new_linker: ?bool = null,
     pie: ?bool = null,
     /// To enable this coverage, one of two things needs to happen:
     /// * The compiler needs to gain the ability to strip only debug info (not symbols)
 @@ -752,6 +753,14 @@ pub const param_sets = [_]CaseParameters{
             .abi = .none,
         },
     },
+    .{
+        .target = .{
+            .cpu_arch = .x86_64,
+            .os_tag = .linux,
+            .abi = .none,
+        },
+        .use_new_linker = true,
+    },
     .{
         .target = .{
             .cpu_arch = .x86_64,
 @@ -761,6 +770,15 @@ pub const param_sets = [_]CaseParameters{
         .use_llvm = true,
         .use_lld = true,
     },
+    .{
+        .target = .{
+            .cpu_arch = .x86_64,
+            .os_tag = .linux,
+            .abi = .none,
+        },
+        .use_llvm = true,
+        .use_new_linker = true,
+    },
     .{
         .target = .{
             .cpu_arch = .x86_64,
 @@ -1175,9 +1193,14 @@ fn addCaseInstance(
     const annotated_case_name = b.fmt("check {s} ({s}{s}{s}{s}{s}{s}{s}{s}{s})", .{
         name,
-        triple orelse "",
+        triple orelse "native",
-        if (triple != null) " " else "",
         backend_string,
+        if (params.use_new_linker == true)
+            " new_linker"
+        else if (params.use_lld == true)
+            " lld"
+        else
+            "",
         if (params.pie == true) " pie" else "",
         if (params.link_libc == true) " libc" else "",
         if (params.linkage) |linkage| switch (linkage) {
 @@ -1210,6 +1233,7 @@ fn addCaseInstance(
         .use_llvm = params.use_llvm,
         .use_lld = params.use_lld,
     });
+    exe.use_new_linker = params.use_new_linker;
     exe.linkage = params.linkage;
     exe.pie = params.pie;
     exe.bundle_ubsan_rt = false;