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-rw-r--r--src/pkg/debug/elf/elf.go2
-rw-r--r--src/pkg/debug/elf/elf_test.go2
-rw-r--r--src/pkg/debug/elf/file.go106
-rw-r--r--src/pkg/debug/elf/file_test.go6
-rw-r--r--src/pkg/debug/elf/testdata/go-relocation-test-clang-x86.objbin0 -> 1900 bytes
-rw-r--r--src/pkg/debug/elf/testdata/hello.c7
6 files changed, 115 insertions, 8 deletions
diff --git a/src/pkg/debug/elf/elf.go b/src/pkg/debug/elf/elf.go
index 03e42b034..d622dae2a 100644
--- a/src/pkg/debug/elf/elf.go
+++ b/src/pkg/debug/elf/elf.go
@@ -517,7 +517,7 @@ const (
DT_INIT_ARRAY DynTag = 25 /* Address of the array of pointers to initialization functions */
DT_FINI_ARRAY DynTag = 26 /* Address of the array of pointers to termination functions */
DT_INIT_ARRAYSZ DynTag = 27 /* Size in bytes of the array of initialization functions. */
- DT_FINI_ARRAYSZ DynTag = 28 /* Size in bytes of the array of terminationfunctions. */
+ DT_FINI_ARRAYSZ DynTag = 28 /* Size in bytes of the array of termination functions. */
DT_RUNPATH DynTag = 29 /* String table offset of a null-terminated library search path string. */
DT_FLAGS DynTag = 30 /* Object specific flag values. */
DT_ENCODING DynTag = 32 /* Values greater than or equal to DT_ENCODING
diff --git a/src/pkg/debug/elf/elf_test.go b/src/pkg/debug/elf/elf_test.go
index 67b961b5c..e3c51bb71 100644
--- a/src/pkg/debug/elf/elf_test.go
+++ b/src/pkg/debug/elf/elf_test.go
@@ -43,7 +43,7 @@ func TestNames(t *testing.T) {
for i, tt := range nameTests {
s := fmt.Sprint(tt.val)
if s != tt.str {
- t.Errorf("#%d: want %q have %q", i, s, tt.str)
+ t.Errorf("#%d: Sprint(%d) = %q, want %q", i, tt.val, s, tt.str)
}
}
}
diff --git a/src/pkg/debug/elf/file.go b/src/pkg/debug/elf/file.go
index a55c37ea9..423932fe0 100644
--- a/src/pkg/debug/elf/file.go
+++ b/src/pkg/debug/elf/file.go
@@ -76,6 +76,9 @@ type Section struct {
func (s *Section) Data() ([]byte, error) {
dat := make([]byte, s.sr.Size())
n, err := s.sr.ReadAt(dat, 0)
+ if n == len(dat) {
+ err = nil
+ }
return dat[0:n], err
}
@@ -412,7 +415,7 @@ func (f *File) getSymbols32(typ SectionType) ([]Symbol, []byte, error) {
if err != nil {
return nil, nil, errors.New("cannot load symbol section")
}
- symtab := bytes.NewBuffer(data)
+ symtab := bytes.NewReader(data)
if symtab.Len()%Sym32Size != 0 {
return nil, nil, errors.New("length of symbol section is not a multiple of SymSize")
}
@@ -455,7 +458,7 @@ func (f *File) getSymbols64(typ SectionType) ([]Symbol, []byte, error) {
if err != nil {
return nil, nil, errors.New("cannot load symbol section")
}
- symtab := bytes.NewBuffer(data)
+ symtab := bytes.NewReader(data)
if symtab.Len()%Sym64Size != 0 {
return nil, nil, errors.New("length of symbol section is not a multiple of Sym64Size")
}
@@ -519,13 +522,17 @@ func (f *File) applyRelocations(dst []byte, rels []byte) error {
if f.Class == ELFCLASS64 && f.Machine == EM_X86_64 {
return f.applyRelocationsAMD64(dst, rels)
}
+ if f.Class == ELFCLASS32 && f.Machine == EM_386 {
+ return f.applyRelocations386(dst, rels)
+ }
return errors.New("not implemented")
}
func (f *File) applyRelocationsAMD64(dst []byte, rels []byte) error {
- if len(rels)%Sym64Size != 0 {
- return errors.New("length of relocation section is not a multiple of Sym64Size")
+ // 24 is the size of Rela64.
+ if len(rels)%24 != 0 {
+ return errors.New("length of relocation section is not a multiple of 24")
}
symbols, _, err := f.getSymbols(SHT_SYMTAB)
@@ -533,7 +540,7 @@ func (f *File) applyRelocationsAMD64(dst []byte, rels []byte) error {
return err
}
- b := bytes.NewBuffer(rels)
+ b := bytes.NewReader(rels)
var rela Rela64
for b.Len() > 0 {
@@ -567,6 +574,43 @@ func (f *File) applyRelocationsAMD64(dst []byte, rels []byte) error {
return nil
}
+func (f *File) applyRelocations386(dst []byte, rels []byte) error {
+ // 8 is the size of Rel32.
+ if len(rels)%8 != 0 {
+ return errors.New("length of relocation section is not a multiple of 8")
+ }
+
+ symbols, _, err := f.getSymbols(SHT_SYMTAB)
+ if err != nil {
+ return err
+ }
+
+ b := bytes.NewReader(rels)
+ var rel Rel32
+
+ for b.Len() > 0 {
+ binary.Read(b, f.ByteOrder, &rel)
+ symNo := rel.Info >> 8
+ t := R_386(rel.Info & 0xff)
+
+ if symNo == 0 || symNo > uint32(len(symbols)) {
+ continue
+ }
+ sym := &symbols[symNo-1]
+
+ if t == R_386_32 {
+ if rel.Off+4 >= uint32(len(dst)) {
+ continue
+ }
+ val := f.ByteOrder.Uint32(dst[rel.Off : rel.Off+4])
+ val += uint32(sym.Value)
+ f.ByteOrder.PutUint32(dst[rel.Off:rel.Off+4], val)
+ }
+ }
+
+ return nil
+}
+
func (f *File) DWARF() (*dwarf.Data, error) {
// There are many other DWARF sections, but these
// are the required ones, and the debug/dwarf package
@@ -600,8 +644,58 @@ func (f *File) DWARF() (*dwarf.Data, error) {
}
}
+ // When using clang we need to process relocations even for 386.
+ rel := f.Section(".rel.debug_info")
+ if rel != nil && rel.Type == SHT_REL && f.Machine == EM_386 {
+ data, err := rel.Data()
+ if err != nil {
+ return nil, err
+ }
+ err = f.applyRelocations(dat[1], data)
+ if err != nil {
+ return nil, err
+ }
+ }
+
abbrev, info, str := dat[0], dat[1], dat[2]
- return dwarf.New(abbrev, nil, nil, info, nil, nil, nil, str)
+ d, err := dwarf.New(abbrev, nil, nil, info, nil, nil, nil, str)
+ if err != nil {
+ return nil, err
+ }
+
+ // Look for DWARF4 .debug_types sections.
+ for i, s := range f.Sections {
+ if s.Name == ".debug_types" {
+ b, err := s.Data()
+ if err != nil && uint64(len(b)) < s.Size {
+ return nil, err
+ }
+
+ for _, r := range f.Sections {
+ if r.Type != SHT_RELA && r.Type != SHT_REL {
+ continue
+ }
+ if int(r.Info) != i {
+ continue
+ }
+ rd, err := r.Data()
+ if err != nil {
+ return nil, err
+ }
+ err = f.applyRelocations(b, rd)
+ if err != nil {
+ return nil, err
+ }
+ }
+
+ err = d.AddTypes(fmt.Sprintf("types-%d", i), b)
+ if err != nil {
+ return nil, err
+ }
+ }
+ }
+
+ return d, nil
}
// Symbols returns the symbol table for f.
diff --git a/src/pkg/debug/elf/file_test.go b/src/pkg/debug/elf/file_test.go
index 38b5f9e70..7f88a54bc 100644
--- a/src/pkg/debug/elf/file_test.go
+++ b/src/pkg/debug/elf/file_test.go
@@ -261,6 +261,12 @@ var relocationTests = []relocationTest{
},
},
{
+ "testdata/go-relocation-test-clang-x86.obj",
+ []relocationTestEntry{
+ {0, &dwarf.Entry{Offset: 0xb, Tag: dwarf.TagCompileUnit, Children: true, Field: []dwarf.Field{{Attr: dwarf.AttrProducer, Val: "clang version google3-trunk (trunk r209387)"}, {Attr: dwarf.AttrLanguage, Val: int64(12)}, {Attr: dwarf.AttrName, Val: "go-relocation-test-clang.c"}, {Attr: dwarf.AttrStmtList, Val: int64(0)}, {Attr: dwarf.AttrCompDir, Val: "/tmp"}}}},
+ },
+ },
+ {
"testdata/gcc-amd64-openbsd-debug-with-rela.obj",
[]relocationTestEntry{
{203, &dwarf.Entry{Offset: 0xc62, Tag: dwarf.TagMember, Children: false, Field: []dwarf.Field{{Attr: dwarf.AttrName, Val: "it_interval"}, {Attr: dwarf.AttrDeclFile, Val: int64(7)}, {Attr: dwarf.AttrDeclLine, Val: int64(236)}, {Attr: dwarf.AttrType, Val: dwarf.Offset(0xb7f)}, {Attr: dwarf.AttrDataMemberLoc, Val: []byte{0x23, 0x0}}}}},
diff --git a/src/pkg/debug/elf/testdata/go-relocation-test-clang-x86.obj b/src/pkg/debug/elf/testdata/go-relocation-test-clang-x86.obj
new file mode 100644
index 000000000..e909cf4e6
--- /dev/null
+++ b/src/pkg/debug/elf/testdata/go-relocation-test-clang-x86.obj
Binary files differ
diff --git a/src/pkg/debug/elf/testdata/hello.c b/src/pkg/debug/elf/testdata/hello.c
new file mode 100644
index 000000000..34d9ee792
--- /dev/null
+++ b/src/pkg/debug/elf/testdata/hello.c
@@ -0,0 +1,7 @@
+#include <stdio.h>
+
+void
+main(int argc, char *argv[])
+{
+ printf("hello, world\n");
+}
generated by cgit v1.2.3 (git 2.46.0) at 2025-09-06 17:06:07 +0000