This reverts r365193 (git commit
194f16b3548bcb23a7f0fd638778ed72edd18d37)
This patch doesn't work with binaries built w/ `--emit-relocs`, e.g.
```
$ echo 'int main() { return 0; }' | clang -Wl,--emit-relocs -x c - -o foo && llvm-objcopy --strip-unneeded foo
llvm-objcopy: error: 'foo': not stripping symbol '__gmon_start__' because it is named in a relocation
```
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@365712
91177308-0d34-0410-b5e6-
96231b3b80d8
FileHeader:
Class: ELFCLASS64
Data: ELFDATA2LSB
- Type: ET_REL
+ Type: ET_EXEC
Machine: EM_X86_64
Sections:
- Name: .text
# BEFORE: Type: PT_LOAD
# BEFORE-NEXT: Offset: 0x240
-# AFTER: SectionHeaderCount: 3
+# AFTER: SectionHeaderCount: 5
# AFTER: Type: PT_LOAD
# AFTER-NEXT: Offset: 0x0
# AFTER: Type: PT_LOAD
# CHECK: }
# CHECK: Section {
# CHECK: Index: 4
+# CHECK: Name: .symtab
+# CHECK: Type: SHT_SYMTAB (0x2)
+# CHECK: Flags [ (0x0)
+# CHECK: ]
+# CHECK: Address: 0x0
+# CHECK: Offset:
+# CHECK: Size:
+# CHECK: Link: 5
+# CHECK: Info: 1
+# CHECK: AddressAlignment: 8
+# CHECK: EntrySize: 24
+# CHECK: }
+# CHECK: Section {
+# CHECK: Index: 5
+# CHECK: Name: .strtab
+# CHECK: Type: SHT_STRTAB (0x3)
+# CHECK: Flags [ (0x0)
+# CHECK: ]
+# CHECK: Address: 0x0
+# CHECK: Offset:
+# CHECK: Size:
+# CHECK: Link: 0
+# CHECK: Info: 0
+# CHECK: AddressAlignment: 1
+# CHECK: EntrySize: 0
+# CHECK: }
+# CHECK: Section {
+# CHECK: Index: 6
# CHECK: Name: .shstrtab
# CHECK: Type: SHT_STRTAB (0x3)
# CHECK: Flags [ (0x0)
Sections:
- Section: .text3
-#CHECK: SectionHeaderCount: 4
+#CHECK: SectionHeaderCount: 6
# CHECK: Sections [
# CHECK-NEXT: Section {
# CHECK-NEXT: }
# CHECK-NEXT: Section {
# CHECK-NEXT: Index: 3
+# CHECK-NEXT: Name: .symtab
+# CHECK-NEXT: Type: SHT_SYMTAB (0x2)
+# CHECK-NEXT: Flags [ (0x0)
+# CHECK-NEXT: ]
+# CHECK-NEXT: Address: 0x0
+# CHECK-NEXT: Offset: 0x3000
+# CHECK-NEXT: Size: 24
+# CHECK-NEXT: Link: 4
+# CHECK-NEXT: Info: 1
+# CHECK-NEXT: AddressAlignment: 8
+# CHECK-NEXT: EntrySize: 24
+# CHECK-NEXT: }
+# CHECK-NEXT: Section {
+# CHECK-NEXT: Index: 4
+# CHECK-NEXT: Name: .strtab
+# CHECK-NEXT: Type: SHT_STRTAB (0x3)
+# CHECK-NEXT: Flags [ (0x0)
+# CHECK-NEXT: ]
+# CHECK-NEXT: Address: 0x0
+# CHECK-NEXT: Offset: 0x3018
+# CHECK-NEXT: Size:
+# CHECK-NEXT: Link: 0
+# CHECK-NEXT: Info: 0
+# CHECK-NEXT: AddressAlignment: 1
+# CHECK-NEXT: EntrySize: 0
+# CHECK-NEXT: }
+# CHECK-NEXT: Section {
+# CHECK-NEXT: Index: 5
# CHECK-NEXT: Name: .shstrtab
# CHECK-NEXT: Type: SHT_STRTAB (0x3)
# CHECK-NEXT: Flags [ (0x0)
# Make sure that when we remove a section we overwrite it with zeros
# DATA: {{^[^[:blank:]]+}} 00 00 00 00
-#CHECK: SectionHeaderCount: 4
+#CHECK: SectionHeaderCount: 6
# CHECK: Sections [
# CHECK: Section {
# CHECK-NEXT: }
# CHECK-NEXT: Section {
# CHECK-NEXT: Index: 3
+# CHECK-NEXT: Name: .symtab
+# CHECK-NEXT: Type: SHT_SYMTAB (0x2)
+# CHECK-NEXT: Flags [ (0x0)
+# CHECK-NEXT: ]
+# CHECK-NEXT: Address: 0x0
+# CHECK-NEXT: Offset:
+# CHECK-NEXT: Size:
+# CHECK-NEXT: Link: 4
+# CHECK-NEXT: Info: 1
+# CHECK-NEXT: AddressAlignment: 8
+# CHECK-NEXT: EntrySize: 24
+# CHECK-NEXT: }
+# CHECK-NEXT: Section {
+# CHECK-NEXT: Index: 4
+# CHECK-NEXT: Name: .strtab
+# CHECK-NEXT: Type: SHT_STRTAB (0x3)
+# CHECK-NEXT: Flags [ (0x0)
+# CHECK-NEXT: ]
+# CHECK-NEXT: Address: 0x0
+# CHECK-NEXT: Offset:
+# CHECK-NEXT: Size:
+# CHECK-NEXT: Link: 0
+# CHECK-NEXT: Info: 0
+# CHECK-NEXT: AddressAlignment: 1
+# CHECK-NEXT: EntrySize: 0
+# CHECK-NEXT: }
+# CHECK-NEXT: Section {
+# CHECK-NEXT: Index: 5
# CHECK-NEXT: Name: .shstrtab
# CHECK-NEXT: Type: SHT_STRTAB (0x3)
# CHECK-NEXT: Flags [ (0x0)
+++ /dev/null
-## Stripping unneeded symbols from execuatble/DSO should
-## eliminate the static symbol table, because it's not used
-## by the dynamic loader.
-
-# RUN: yaml2obj %s > %t
-# RUN: cp %t %t1
-# RUN: llvm-objcopy --strip-unneeded %t %t2
-# RUN: llvm-readobj --section-headers %t2 | FileCheck %s
-
-!ELF
-FileHeader:
- Class: ELFCLASS64
- Data: ELFDATA2LSB
- Type: ET_EXEC
- Machine: EM_X86_64
-Symbols:
- - Name: bar
- - Name: foo
- Binding: STB_GLOBAL
-
-# CHECK-NOT: .symtab
if ((Config.StripUnneeded ||
is_contained(Config.UnneededSymbolsToRemove, Sym.Name)) &&
- (!Obj.isRelocatable() || isUnneededSymbol(Sym)))
+ isUnneededSymbol(Sym))
return true;
// We want to remove undefined symbols if all references have been stripped.
return Buf.commit();
}
-static Error removeUnneededSections(Object &Obj) {
- // We can remove an empty symbol table from non-relocatable objects.
- // Relocatable objects typically have relocation sections whose
- // sh_link field points to .symtab, so we can't remove .symtab
- // even if it is empty.
- if (Obj.isRelocatable() || Obj.SymbolTable == nullptr ||
- !Obj.SymbolTable->empty())
- return Error::success();
-
- // .strtab can be used for section names. In such a case we shouldn't
- // remove it.
- auto *StrTab = Obj.SymbolTable->getStrTab() == Obj.SectionNames
- ? nullptr
- : Obj.SymbolTable->getStrTab();
- return Obj.removeSections(false, [&](const SectionBase &Sec) {
- return &Sec == Obj.SymbolTable || &Sec == StrTab;
- });
-}
-
template <class ELFT> Error ELFWriter<ELFT>::finalize() {
// It could happen that SectionNames has been removed and yet the user wants
// a section header table output. We need to throw an error if a user tries
"cannot write section header table because "
"section header string table was removed");
- if (Error E = removeUnneededSections(Obj))
- return E;
Obj.sortSections();
// We need to assign indexes before we perform layout because we need to know
Segments.emplace_back(llvm::make_unique<Segment>(Data));
return *Segments.back();
}
- bool isRelocatable() const {
- return Type != ELF::ET_DYN && Type != ELF::ET_EXEC;
- }
};
} // end namespace elf
projects / llvm / commitdiff