[ELF] Define __start_XXX/__stop_XXX symbols where XXX is a section name

This is GNU ELF linker extension used particularly by LibC code.
If input object files contain section named XXX, and the XXX is a valid C
identifier, and there are undefined or weak symbols __start_XXX/__stop_XXX,
linker should define __start_XXX/__stop_XXX symbols point to the begin/end
of the XXX section correspondingly.

For example, without support of this extension statically linked executables
for X86_64 and Mips (maybe other) targets do not flush IO buffers at the end
of executing.

llvm-svn: 241341

1 files changed, 2 insertions, 0 deletions

diff --git a/lld/lib/ReaderWriter/ELF/ARM/ARMExecutableWriter.h b/lld/lib/ReaderWriter/ELF/ARM/ARMExecutableWriter.h
index 45e0aff1f18..974dab63a12 100644
--- a/lld/lib/ReaderWriter/ELF/ARM/ARMExecutableWriter.h
+++ b/lld/lib/ReaderWriter/ELF/ARM/ARMExecutableWriter.h
@@ -50,6 +50,8 @@ void ARMExecutableWriter::createImplicitFiles(
 
 void ARMExecutableWriter::processUndefinedSymbol(
     StringRef symName, RuntimeFile<ELF32LE> &file) const {
+  ARMELFWriter<ExecutableWriter<ELF32LE>>::processUndefinedSymbol(symName,
+                                                                  file);
   if (symName == gotSymbol) {
     file.addAbsoluteAtom(gotSymbol);
   } else if (symName.startswith("__exidx")) {