Merge root: Revert Add github lockdown app to auto-close pull requests.

apple-llvm-split-dir: -

Author: apple-llvm-mt

.github/lockdown.yml

@@ -7,6 +7,7 @@
 // RUN: %test_debuginfo %s %t.out
 //
 // PR34513
+void __attribute__((noinline)) stop() {}
 
 struct string {
   string() {}
@@ -17,7 +18,8 @@ struct string {
 string get_string() {
   string unused;
   string result = 3;
-  // DEBUGGER: break 21
+  // DEBUGGER: break 22
+  stop();
   return result;
 }
 void some_function(int) {}
@@ -32,7 +34,8 @@ string2 get_string2() {
   some_function(result.i);
   // Test that the debugger can get the value of result after another
   // function is called.
-  // DEBUGGER: break 35
+  // DEBUGGER: break 38
+  stop();
   return result;
 }
 int main() {

debuginfo-tests/nrvo-string.cpp

@@ -115,7 +115,7 @@ struct Configuration {
   // Symbols in this set are considered as live by the garbage collector.
   std::vector<Symbol *> GCRoot;
 
-  std::set<StringRef> NoDefaultLibs;
+  std::set<std::string> NoDefaultLibs;
   bool NoDefaultLibAll = false;
 
   // True if we are creating a DLL.

lld/COFF/Config.h

@@ -356,7 +356,7 @@ void LinkerDriver::parseDirectives(InputFile *File) {
       parseMerge(Arg->getValue());
       break;
     case OPT_nodefaultlib:
-      Config->NoDefaultLibs.insert(doFindLib(Arg->getValue()));
+      Config->NoDefaultLibs.insert(doFindLib(Arg->getValue()).lower());
       break;
     case OPT_section:
       parseSection(Arg->getValue());
@@ -457,7 +457,7 @@ Optional<StringRef> LinkerDriver::findLib(StringRef Filename) {
     return None;
 
   StringRef Path = doFindLib(Filename);
-  if (Config->NoDefaultLibs.count(Path))
+  if (Config->NoDefaultLibs.count(Path.lower()))
     return None;
 
   if (Optional<sys::fs::UniqueID> ID = getUniqueID(Path))
@@ -1240,7 +1240,7 @@ void LinkerDriver::link(ArrayRef<const char *> ArgsArr) {
 
   // Handle /nodefaultlib:<filename>
   for (auto *Arg : Args.filtered(OPT_nodefaultlib))
-    Config->NoDefaultLibs.insert(doFindLib(Arg->getValue()));
+    Config->NoDefaultLibs.insert(doFindLib(Arg->getValue()).lower());
 
   // Handle /nodefaultlib
   if (Args.hasArg(OPT_nodefaultlib_all))

lld/COFF/Driver.cpp

@@ -92,21 +92,20 @@ LLDDwarfObj<ELFT>::findAux(const InputSectionBase &Sec, uint64_t Pos,
   const typename ELFT::Sym &Sym = File->template getELFSyms<ELFT>()[SymIndex];
   uint32_t SecIndex = File->getSectionIndex(Sym);
 
-  // Broken debug info can point to a non-Defined symbol.
-  auto *DR = dyn_cast<Defined>(&File->getRelocTargetSym(Rel));
-  if (!DR) {
-    RelType Type = Rel.getType(Config->IsMips64EL);
-    if (Type != Target->NoneRel)
-      error(toString(File) + ": relocation " + lld::toString(Type) + " at 0x" +
-            llvm::utohexstr(Rel.r_offset) + " has unsupported target");
-    return None;
-  }
-  uint64_t Val = DR->Value;
+  // An undefined symbol may be a symbol defined in a discarded section. We
+  // shall still resolve it. This is important for --gdb-index: the end address
+  // offset of an entry in .debug_ranges is relocated. If it is not resolved,
+  // its zero value will terminate the decoding of .debug_ranges prematurely.
+  Symbol &S = File->getRelocTargetSym(Rel);
+  uint64_t Val = 0;
+  if (auto *DR = dyn_cast<Defined>(&S)) {
+    Val = DR->Value;
 
-  // FIXME: We should be consistent about always adding the file
-  // offset or not.
-  if (DR->Section->Flags & ELF::SHF_ALLOC)
-    Val += cast<InputSection>(DR->Section)->getOffsetInFile();
+    // FIXME: We should be consistent about always adding the file
+    // offset or not.
+    if (DR->Section->Flags & ELF::SHF_ALLOC)
+      Val += cast<InputSection>(DR->Section)->getOffsetInFile();
+  }
 
   DataRefImpl D;
   D.p = getAddend<ELFT>(Rel);

lld/ELF/DWARF.cpp

@@ -1080,6 +1080,9 @@ template <class ELFT> void ObjFile<ELFT>::initializeSymbols() {
 
       if (ESym.st_shndx == SHN_UNDEF)
         this->Symbols[I] = make<Undefined>(this, Name, Binding, StOther, Type);
+      else if (Sec == &InputSection::Discarded)
+        this->Symbols[I] = make<Undefined>(this, Name, Binding, StOther, Type,
+                                           /*DiscardedSecIdx=*/SecIdx);
       else
         this->Symbols[I] =
             make<Defined>(this, Name, Binding, StOther, Type, Value, Size, Sec);

lld/ELF/InputFiles.cpp

@@ -412,7 +412,8 @@ void InputSection::copyRelocations(uint8_t *Buf, ArrayRef<RelTy> Rels) {
 
   for (const RelTy &Rel : Rels) {
     RelType Type = Rel.getType(Config->IsMips64EL);
-    Symbol &Sym = getFile<ELFT>()->getRelocTargetSym(Rel);
+    const ObjFile<ELFT> *File = getFile<ELFT>();
+    Symbol &Sym = File->getRelocTargetSym(Rel);
 
     auto *P = reinterpret_cast<typename ELFT::Rela *>(Buf);
     Buf += sizeof(RelTy);
@@ -435,10 +436,23 @@ void InputSection::copyRelocations(uint8_t *Buf, ArrayRef<RelTy> Rels) {
       // .eh_frame is horribly special and can reference discarded sections. To
       // avoid having to parse and recreate .eh_frame, we just replace any
       // relocation in it pointing to discarded sections with R_*_NONE, which
-      // hopefully creates a frame that is ignored at runtime.
+      // hopefully creates a frame that is ignored at runtime. Also, don't warn
+      // on .gcc_except_table and debug sections.
+      //
+      // See the comment in maybeReportUndefined for PPC64 .toc .
       auto *D = dyn_cast<Defined>(&Sym);
       if (!D) {
-        error("STT_SECTION symbol should be defined");
+        if (!Sec->Name.startswith(".debug") &&
+            !Sec->Name.startswith(".zdebug") && Sec->Name != ".eh_frame" &&
+            Sec->Name != ".gcc_except_table" && Sec->Name != ".toc") {
+          uint32_t SecIdx = cast<Undefined>(Sym).DiscardedSecIdx;
+          Elf_Shdr_Impl<ELFT> Sec =
+              CHECK(File->getObj().sections(), File)[SecIdx];
+          warn("relocation refers to a discarded section: " +
+               CHECK(File->getObj().getSectionName(&Sec), File) +
+               "\n>>> referenced by " + getObjMsg(P->r_offset));
+        }
+        P->setSymbolAndType(0, 0, false);
         continue;
       }
       SectionBase *Section = D->Section->Repl;

lld/ELF/InputSection.cpp

@@ -653,9 +653,17 @@ static std::string maybeReportDiscarded(Undefined &Sym) {
     return "";
   ArrayRef<Elf_Shdr_Impl<ELFT>> ObjSections =
       CHECK(File->getObj().sections(), File);
-  std::string Msg =
-      "relocation refers to a symbol in a discarded section: " + toString(Sym) +
-      "\n>>> defined in " + toString(File);
+
+  std::string Msg;
+  if (Sym.Type == ELF::STT_SECTION) {
+    Msg = "relocation refers to a discarded section: ";
+    Msg += CHECK(
+        File->getObj().getSectionName(&ObjSections[Sym.DiscardedSecIdx]), File);
+  } else {
+    Msg = "relocation refers to a symbol in a discarded section: " +
+          toString(Sym);
+  }
+  Msg += "\n>>> defined in " + toString(File);
 
   Elf_Shdr_Impl<ELFT> ELFSec = ObjSections[Sym.DiscardedSecIdx - 1];
   if (ELFSec.sh_type != SHT_GROUP)

lld/ELF/Relocations.cpp

@@ -48,17 +48,11 @@ static uint64_t getSymVA(const Symbol &Sym, int64_t &Addend) {
     auto &D = cast<Defined>(Sym);
     SectionBase *IS = D.Section;
 
-    // According to the ELF spec reference to a local symbol from outside
-    // the group are not allowed. Unfortunately .eh_frame breaks that rule
-    // and must be treated specially. For now we just replace the symbol with
-    // 0.
-    if (IS == &InputSection::Discarded)
-      return 0;
-
     // This is an absolute symbol.
     if (!IS)
       return D.Value;
 
+    assert(IS != &InputSection::Discarded);
     IS = IS->Repl;
 
     uint64_t Offset = D.Value;

lld/ELF/Symbols.cpp

@@ -29,3 +29,10 @@ CHECK3-NEXT: >>> referenced by {{.*}}hello64.obj:(main)
 
 # RUN: env LIB=%T lld-link /out:%t.exe /entry:main \
 # RUN:   /subsystem:console hello64.obj /defaultlib:std64.lib
+
+MSVC stamps uppercase references in OBJ directives, thus ensure that passing lowercase 'libcmt' and 'oldnames' to /nodefaultlib works.
+# RUN: lld-link %S/Inputs/precomp.obj %S/Inputs/precomp-a.obj %S/Inputs/precomp-b.obj /nodefaultlib:libcmt /nodefaultlib:oldnames /entry:main /debug /pdb:%t.pdb /out:%t.exe /opt:ref /opt:icf
+# RUN: llvm-pdbutil dump -modules %t.pdb | FileCheck %s -check-prefix UPPERCASE
+
+UPPERCASE-NOT: OLDNAMES
+UPPERCASE-NOT: LIBCMT

lld/test/COFF/nodefaultlib.test

@@ -1,6 +1,8 @@
-.section .text.bar1,"aG",@progbits,group,comdat
+.global bar, _start
 
-.section .text.bar2
-.global bar
-bar:
- .quad .text.bar1
+.section .text.foo,"aG",@progbits,group,comdat
+
+.section .text
+_start:
+ .quad .text.foo
+ .quad bar

lld/test/ELF/Inputs/comdat-discarded-reloc.s

@@ -5,14 +5,24 @@
 # RUN: echo '.section .text.foo,"axG",@progbits,foo,comdat; .globl bar; bar:' |\
 # RUN:   llvm-mc -filetype=obj -triple=x86_64 - -o %t3.o
 
-# RUN: not ld.lld %t1.o %t2.o %t3.o -o /dev/null 2>&1 | FileCheck %s
+# RUN: not ld.lld %t2.o %t3.o %t1.o -o /dev/null 2>&1 | FileCheck %s
 
 # CHECK:      error: relocation refers to a symbol in a discarded section: bar
 # CHECK-NEXT: >>> defined in {{.*}}3.o
 # CHECK-NEXT: >>> section group signature: foo
 # CHECK-NEXT: >>> prevailing definition is in {{.*}}2.o
 # CHECK-NEXT: >>> referenced by {{.*}}1.o:(.text+0x1)
 
+# CHECK:      error: relocation refers to a discarded section: .text.foo
+# CHECK-NEXT: >>> defined in {{.*}}1.o
+# CHECK-NEXT: >>> section group signature: foo
+# CHECK-NEXT: >>> prevailing definition is in {{.*}}2.o
+# CHECK-NEXT: >>> referenced by {{.*}}1.o:(.data+0x0)
+
 .globl _start
 _start:
   jmp bar
+
+.section .text.foo,"axG",@progbits,foo,comdat
+.data
+  .quad .text.foo

lld/test/ELF/comdat-discarded-error.s

@@ -0,0 +1,63 @@
+# REQUIRES: x86
+# RUN: llvm-mc -filetype=obj -triple=x86_64 %s -o %t.o
+# RUN: ld.lld --gdb-index %t.o %t.o -o %t
+
+## .debug_info has a relocation to .text.foo . The second %t.o is discarded.
+## Check we don't error on the relocation.
+# CHECK: .rela.debug_info {
+# CHECK-NEXT: 0xC R_X86_64_64 .text.foo 0x0
+
+.section .text.foo,"axG",@progbits,foo,comdat
+.globl foo
+.Lfunc_begin0:
+foo:
+  ret
+.Lfunc_end0:
+
+.section .debug_abbrev,"",@progbits
+  .byte   1       # Abbreviation Code
+  .byte   17      # DW_TAG_compile_unit
+  .byte   1       # DW_CHILDREN_yes
+  .byte   17      # DW_AT_low_pc
+  .byte   1       # DW_FORM_addr
+  .byte   18      # DW_AT_high_pc
+  .byte   6       # DW_FORM_data4
+  .ascii  "\264B" # DW_AT_GNU_pubnames
+  .byte   25      # DW_FORM_flag_present
+  .byte   0       # EOM(1)
+  .byte   0       # EOM(2)
+  .byte   2       # Abbreviation Code
+  .byte   46      # DW_TAG_subprogram
+  .byte   0       # DW_CHILDREN_no
+  .byte   3       # DW_AT_name
+  .byte   8       # DW_FORM_string
+  .byte   0       # EOM(1)
+  .byte   0       # EOM(2)
+  .byte   0
+
+.section .debug_info,"",@progbits
+.Lcu_begin0:
+  .long   .Lcu_end0 - .Lcu_begin0 - 4
+  .short  4              # DWARF version number
+  .long   0              # Offset Into Abbrev. Section
+  .byte   4              # Address Size
+.Ldie0:
+  .byte   1              # Abbrev [1] DW_TAG_compile_unit
+  .quad   .Lfunc_begin0  # DW_AT_low_pc
+  .long   .Lfunc_end0 - .Lfunc_begin0 # DW_AT_high_pc
+  .byte   2              # Abbrev [2] DW_TAG_subprogram
+  .asciz  "foo"          # DW_AT_name
+  .byte   0
+.Lcu_end0:
+
+.section .debug_gnu_pubnames,"",@progbits
+  .long   .LpubNames_end0 - .LpubNames_begin0
+.LpubNames_begin0:
+  .short  2              # Version
+  .long   .Lcu_begin0    # CU Offset
+  .long   .Lcu_end0 - .Lcu_begin0
+  .long   .Ldie0 - .Lcu_begin0
+  .byte   48             # Attributes: FUNCTION, EXTERNAL
+  .asciz  "foo"          # External Name
+  .long   0
+.LpubNames_end0:

lld/test/ELF/comdat-discarded-gdb-index.s

@@ -1,17 +1,42 @@
 # REQUIRES: x86
 # RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
 # RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %p/Inputs/comdat-discarded-reloc.s -o %t2.o
-# RUN: ld.lld -gc-sections %t.o %t2.o -o %t
+# RUN: ld.lld -gc-sections --noinhibit-exec %t2.o %t.o -o /dev/null
+# RUN: ld.lld -r %t2.o %t.o -o %t 2>&1 | FileCheck --check-prefix=WARN %s
+# RUN: llvm-readobj -r %t | FileCheck --check-prefix=RELOC %s
 
 ## ELF spec doesn't allow a relocation to point to a deduplicated
 ## COMDAT section. Unfortunately this happens in practice (e.g. .eh_frame)
 ## Test case checks we do not crash.
 
-.global bar, _start
+# WARN: warning: relocation refers to a discarded section: .text.bar1
+# WARN-NEXT: >>> referenced by {{.*}}.o:(.rela.text.bar2+0x0)
+# WARN-NOT: warning
 
-.section .text.foo,"aG",@progbits,group,comdat
+# RELOC:      .rela.eh_frame {
+# RELOC-NEXT:   R_X86_64_NONE
+# RELOC-NEXT: }
+# RELOC-NEXT: .rela.debug_foo {
+# RELOC-NEXT:   R_X86_64_NONE
+# RELOC-NEXT: }
+# RELOC-NEXT: .rela.gcc_except_table {
+# RELOC-NEXT:   R_X86_64_NONE
+# RELOC-NEXT: }
 
-.section .text
-_start:
- .quad .text.foo
- .quad bar
+.section .text.bar1,"aG",@progbits,group,comdat
+
+## .text.bar1 in this file is discarded. Warn on the relocation.
+.section .text.bar2,"ax"
+.globl bar
+bar:
+  .quad .text.bar1
+
+## Don't warn on .eh_frame, .debug*, .zdebug*, or .gcc_except_table
+.section .eh_frame,"a"
+  .quad .text.bar1
+
+.section .debug_foo
+  .quad .text.bar1
+
+.section .gcc_except_table,"a"
+  .quad .text.bar1