[PATCH] [lld][ELF] Add linker script ENTRY command

[Rui Ueyama]

   bool Driver::link(TargetInfo targetInfo, const std::vector<LinkerInput> &inputs, raw_ostream &diagnostics);

  Got it and agreed. That signature turned out that it doesn't really work because object slicing of targetInfo, so I'll change this slightly. I'll move LinkerInputs out of TargetInfo in a different patch.


================
Comment at: include/lld/Core/TargetInfo.h:248-257
@@ -247,2 +247,12 @@
 
+  /// This method is called by core linking to fix missing options that were
+  /// not specified by linker script or object file.
+  ///
+  /// On GNU, many linker options can be specified by linker script. On
+  /// Windows, object files may contain linker options. Because of that
+  /// reason, we do not have a complete list of linker options until all input
+  /// files are parsed. This method is supposed to set missing options that
+  /// were not specified neither by command line nor linker script or object
+  /// file.
+  virtual void maybeSetDefaultOptions() { };
 
----------------
Shankar Kalpathi Easwaran wrote:
> This should not be in the base TargetInfo class and the function not exposed to the user. 
I will remove this method and leave _entrySymbolName empty. We can compute this value when it's really needed.

================
Comment at: lib/ReaderWriter/ReaderLinkerScript.cpp:85
@@ -84,3 +84,3 @@
                             std::vector<std::unique_ptr<File> > &result) const {
   auto lsf = LinkerScriptFile::create(_targetInfo, std::move(mb));
   if (!lsf)
----------------
Shankar Kalpathi Easwaran wrote:
> The _targetInfo should be changed to _elfTargetInfo I think.
LinkerScript does not use ELFTargetInfo-specific methods or fields, so this seems ok.


http://llvm-reviews.chandlerc.com/D833

BRANCH
  linker-script-entry

ARCANIST PROJECT
  lld