4 files changed, 25 insertions, 3 deletions
diff --git a/lld/COFF/Chunks.cpp b/lld/COFF/Chunks.cpp
index 1d5ae5571d2..56124acaf9a 100644
--- a/lld/COFF/Chunks.cpp
+++ b/lld/COFF/Chunks.cpp
@@ -52,6 +52,15 @@ static void add32(uint8_t *P, int32_t V) { write32le(P, read32le(P) + V); }
 static void add64(uint8_t *P, int64_t V) { write64le(P, read64le(P) + V); }
 static void or16(uint8_t *P, uint16_t V) { write16le(P, read16le(P) | V); }
 
+static void applySecRel(const SectionChunk *Sec, uint8_t *Off, Defined *Sym) {
+  // Don't apply section relative relocations to absolute symbols in codeview
+  // debug info sections. MSVC does not treat such relocations as fatal errors,
+  // and they can be found in the standard library for linker-provided symbols
+  // like __guard_fids_table and __safe_se_handler_table.
+  if (!(isa<DefinedAbsolute>(Sym) && Sec->isCodeView()))
+    add32(Off, Sym->getSecrel());
+}
+
 void SectionChunk::applyRelX64(uint8_t *Off, uint16_t Type, Defined *Sym,
                                uint64_t P) const {
   uint64_t S = Sym->getRVA();
@@ -66,7 +75,7 @@ void SectionChunk::applyRelX64(uint8_t *Off, uint16_t Type, Defined *Sym,
   case IMAGE_REL_AMD64_REL32_4:  add32(Off, S - P - 8); break;
   case IMAGE_REL_AMD64_REL32_5:  add32(Off, S - P - 9); break;
   case IMAGE_REL_AMD64_SECTION:  add16(Off, Sym->getSectionIndex()); break;
-  case IMAGE_REL_AMD64_SECREL:   add32(Off, Sym->getSecrel()); break;
+  case IMAGE_REL_AMD64_SECREL:   applySecRel(this, Off, Sym); break;
   default:
     fatal("unsupported relocation type 0x" + Twine::utohexstr(Type));
   }
@@ -81,7 +90,7 @@ void SectionChunk::applyRelX86(uint8_t *Off, uint16_t Type, Defined *Sym,
   case IMAGE_REL_I386_DIR32NB:  add32(Off, S); break;
   case IMAGE_REL_I386_REL32:    add32(Off, S - P - 4); break;
   case IMAGE_REL_I386_SECTION:  add16(Off, Sym->getSectionIndex()); break;
-  case IMAGE_REL_I386_SECREL:   add32(Off, Sym->getSecrel()); break;
+  case IMAGE_REL_I386_SECREL:   applySecRel(this, Off, Sym); break;
   default:
     fatal("unsupported relocation type 0x" + Twine::utohexstr(Type));
   }
@@ -141,7 +150,7 @@ void SectionChunk::applyRelARM(uint8_t *Off, uint16_t Type, Defined *Sym,
   case IMAGE_REL_ARM_BRANCH20T: applyBranch20T(Off, S - P - 4); break;
   case IMAGE_REL_ARM_BRANCH24T: applyBranch24T(Off, S - P - 4); break;
   case IMAGE_REL_ARM_BLX23T:    applyBranch24T(Off, S - P - 4); break;
-  case IMAGE_REL_ARM_SECREL:    add32(Off, Sym->getSecrel()); break;
+  case IMAGE_REL_ARM_SECREL:    applySecRel(this, Off, Sym); break;
   default:
     fatal("unsupported relocation type 0x" + Twine::utohexstr(Type));
   }
diff --git a/lld/COFF/Symbols.cpp b/lld/COFF/Symbols.cpp
index 5c185a511dd..1cf2934a355 100644
--- a/lld/COFF/Symbols.cpp
+++ b/lld/COFF/Symbols.cpp
@@ -61,6 +61,8 @@ COFFSymbolRef DefinedCOFF::getCOFFSymbol() {
   return COFFSymbolRef(reinterpret_cast<const coff_symbol32 *>(Sym));
 }
 
+uint16_t DefinedAbsolute::OutputSectionIndex = 0;
+
 static Chunk *makeImportThunk(DefinedImportData *S, uint16_t Machine) {
   if (Machine == AMD64)
     return make<ImportThunkChunkX64>(S);
diff --git a/lld/COFF/Symbols.h b/lld/COFF/Symbols.h
index 801fc87f91d..828744b8ff3 100644
--- a/lld/COFF/Symbols.h
+++ b/lld/COFF/Symbols.h
@@ -212,6 +212,11 @@ public:
   uint64_t getRVA() { return VA - Config->ImageBase; }
   void setVA(uint64_t V) { VA = V; }
 
+  // The sentinel absolute symbol section index. Section index relocations
+  // against absolute symbols resolve to this 16 bit number, and it is the
+  // largest valid section index plus one. This is written by the Writer.
+  static uint16_t OutputSectionIndex;
+
 private:
   uint64_t VA;
 };
diff --git a/lld/COFF/Writer.cpp b/lld/COFF/Writer.cpp
index d31f0c3d57a..c67fac59f92 100644
--- a/lld/COFF/Writer.cpp
+++ b/lld/COFF/Writer.cpp
@@ -219,6 +219,8 @@ uint64_t Defined::getSecrel() {
 uint64_t Defined::getSectionIndex() {
   if (auto *D = dyn_cast<DefinedRegular>(this))
     return D->getChunk()->getOutputSection()->SectionIndex;
+  if (auto *D = dyn_cast<DefinedAbsolute>(this))
+    return DefinedAbsolute::OutputSectionIndex;
   fatal("SECTION relocation points to a non-regular symbol: " +
         toString(*this));
 }
@@ -775,6 +777,10 @@ void Writer::setSectionPermissions() {
 
 // Write section contents to a mmap'ed file.
 void Writer::writeSections() {
+  // Record the section index that should be used when resolving a section
+  // relocation against an absolute symbol.
+  DefinedAbsolute::OutputSectionIndex = OutputSections.size() + 1;
+
   uint8_t *Buf = Buffer->getBufferStart();
   for (OutputSection *Sec : OutputSections) {
     uint8_t *SecBuf = Buf + Sec->getFileOff();