--- /dev/null
+## Here we want to check that llvm-objcopy removes an undefined symbol
+## if all references to it have been stripped.
+
+# RUN: yaml2obj --docnum=1 %s -o %t.o
+# RUN: llvm-objcopy -j .other.section %t.o %t2.o
+# RUN: llvm-readobj --symbols %t2.o | FileCheck %s --implicit-check-not=bar
+
+# RUN: llvm-objcopy -j .text -j .rela.text1 %t.o %t2.o
+# RUN: llvm-readobj --symbols %t2.o | FileCheck %s --check-prefix=BAR
+
+# BAR: bar
+
+--- !ELF
+FileHeader:
+ Class: ELFCLASS64
+ Data: ELFDATA2LSB
+ Type: ET_REL
+ Machine: EM_X86_64
+Sections:
+ - Name: .text
+ Type: SHT_PROGBITS
+ - Name: .rela.text1
+ Type: SHT_RELA
+ Relocations:
+ - Offset: 0x0000000000000001
+ Symbol: bar
+ Type: R_X86_64_32
+ - Name: .rela.text2
+ Type: SHT_RELA
+ Relocations:
+ - Offset: 0x0000000000000001
+ Symbol: bar
+ Type: R_X86_64_32
+ - Name: .other.section
+ Type: SHT_PROGBITS
+Symbols:
+ - Name: bar
+ Binding: STB_GLOBAL
+...
+
+## Check we remove unreferenced undefined symbols, even if
+## they weren't previously referenced. This follows GNU.
+
+# RUN: yaml2obj --docnum=2 %s -o %t.o
+# RUN: llvm-objcopy -j .keep_me %t.o %t2.o
+# RUN: llvm-readobj --symbols %t2.o | FileCheck %s --implicit-check-not=bar
+
+--- !ELF
+FileHeader:
+ Class: ELFCLASS64
+ Data: ELFDATA2LSB
+ Type: ET_REL
+ Machine: EM_X86_64
+Sections:
+ - Name: .keep_me
+ Type: SHT_PROGBITS
+Symbols:
+ - Name: bar
+ Binding: STB_GLOBAL
+...
// The purpose of this loop is to mark symbols referenced by sections
// (like GroupSection or RelocationSection). This way, we know which
// symbols are still 'needed' and which are not.
- if (Config.StripUnneeded || !Config.UnneededSymbolsToRemove.empty()) {
+ if (Config.StripUnneeded || !Config.UnneededSymbolsToRemove.empty() ||
+ !Config.OnlySection.empty()) {
for (auto &Section : Obj.sections())
Section.markSymbols();
}
isUnneededSymbol(Sym))
return true;
+ // We want to remove undefined symbols if all references have been stripped.
+ if (!Config.OnlySection.empty() && !Sym.Referenced &&
+ Sym.getShndx() == SHN_UNDEF)
+ return true;
+
return false;
};