diff options
| author | George Rimar <grimar@accesssoftek.com> | 2018-12-10 09:24:49 +0000 |
|---|---|---|
| committer | George Rimar <grimar@accesssoftek.com> | 2018-12-10 09:24:49 +0000 |
| commit | d37aa05d4433830d4f1b22b5a600c5bc04e0c1ea (patch) | |
| tree | a6feb8ecd215682b57fbb35dceb95db95a3a4b57 | |
| parent | b827cb61df9f60bda803337106f78ef1909a8c5c (diff) | |
[LLD][ELF] - Support discarding the .dynamic section.
This is a part of https://bugs.llvm.org/show_bug.cgi?id=39810.
Seems it turns out that supporting /DISCARD/ for the .dynamic section with the
linker script is something we can do easily. The patch does this.
Differential revision: https://reviews.llvm.org/D55211
| -rw-r--r-- | lld/ELF/LinkerScript.cpp | 3 | ||||
| -rw-r--r-- | lld/ELF/Writer.cpp | 7 | ||||
| -rw-r--r-- | lld/test/ELF/linkerscript/discard-section-err.s | 5 |
3 files changed, 6 insertions, 9 deletions
diff --git a/lld/ELF/LinkerScript.cpp b/lld/ELF/LinkerScript.cpp index e37b4a38e8d..fbc02541620 100644 --- a/lld/ELF/LinkerScript.cpp +++ b/lld/ELF/LinkerScript.cpp @@ -415,8 +415,7 @@ LinkerScript::computeInputSections(const InputSectionDescription *Cmd) { void LinkerScript::discard(ArrayRef<InputSection *> V) { for (InputSection *S : V) { - if (S == In.ShStrTab || S == In.Dynamic || S == In.RelaDyn || - S == In.RelrDyn) + if (S == In.ShStrTab || S == In.RelaDyn || S == In.RelrDyn) error("discarding " + S->Name + " section is not allowed"); // You can discard .hash and .gnu.hash sections by linker scripts. Since diff --git a/lld/ELF/Writer.cpp b/lld/ELF/Writer.cpp index 64f4f655257..5eed0184ecd 100644 --- a/lld/ELF/Writer.cpp +++ b/lld/ELF/Writer.cpp @@ -1621,7 +1621,7 @@ template <class ELFT> void Writer<ELFT>::finalizeSections() { // It should be okay as no one seems to care about the type. // Even the author of gold doesn't remember why gold behaves that way. // https://sourceware.org/ml/binutils/2002-03/msg00360.html - if (In.DynSymTab) + if (In.Dynamic->Parent) Symtab->addDefined("_DYNAMIC", STV_HIDDEN, STT_NOTYPE, 0 /*Value*/, /*Size=*/0, STB_WEAK, In.Dynamic, /*File=*/nullptr); @@ -1935,9 +1935,8 @@ template <class ELFT> std::vector<PhdrEntry *> Writer<ELFT>::createPhdrs() { Ret.push_back(TlsHdr); // Add an entry for .dynamic. - if (In.DynSymTab) - AddHdr(PT_DYNAMIC, In.Dynamic->getParent()->getPhdrFlags()) - ->add(In.Dynamic->getParent()); + if (OutputSection *Sec = In.Dynamic->getParent()) + AddHdr(PT_DYNAMIC, Sec->getPhdrFlags())->add(Sec); // PT_GNU_RELRO includes all sections that should be marked as // read-only by dynamic linker after proccessing relocations. diff --git a/lld/test/ELF/linkerscript/discard-section-err.s b/lld/test/ELF/linkerscript/discard-section-err.s index 82105b514a1..bb77dbb087d 100644 --- a/lld/test/ELF/linkerscript/discard-section-err.s +++ b/lld/test/ELF/linkerscript/discard-section-err.s @@ -7,10 +7,9 @@ # RUN: FileCheck -check-prefix=SHSTRTAB %s # SHSTRTAB: discarding .shstrtab section is not allowed +## We allow discarding .dynamic, check we don't crash. # RUN: echo "SECTIONS { /DISCARD/ : { *(.dynamic) } }" > %t.script -# RUN: not ld.lld -pie -o %t --script %t.script %t.o 2>&1 | \ -# RUN: FileCheck -check-prefix=DYNAMIC %s -# DYNAMIC: discarding .dynamic section is not allowed +# RUN: ld.lld -pie -o %t --script %t.script %t.o ## We allow discarding .dynsym, check we don't crash. # RUN: echo "SECTIONS { /DISCARD/ : { *(.dynsym) } }" > %t.script |