[ELF] Use search paths for --version-script=

[MaskRay]

Summary

This behavior matches ld.bfd -Ld --version-script=t.script a.o

[ruiu]

LGTM

test/ELF/version-script-in-search-path.s

9

For safety, you should use %T/searchpath/%t.script instead of %T/searchpath/t.script because this line can succeed if there's other test that happens to create t.script in the current directory.

[ruiu]

Looks like you forgot to apply the change that I proposed.

[MaskRay]

test/ELF/version-script-in-search-path.s

9

Sorry I didn't notice this comment when committing.

%t.script is an absolute path so it does not work here --version-script=%t.script

[ruiu]

You could use %basename_t. I did it in r337972 for you.

[MaskRay]

In D49820#1175889, @ruiu wrote:

You could use %basename_t. I did it in r337972 for you.

Thanks! And good to know this substitution (defined in utils/lit/lit/TestRunner.py). I did the same for test/ELF/linkerscript/linker-script-in-search-path.s

ELF/Driver.h

 #include "Options.inc"
 #undef OPTION
 };
 
 void printHelp();
 std::string createResponseFile(const llvm::opt::InputArgList &Args);
 
 llvm::Optional<std::string> findFromSearchPaths(StringRef Path);
-llvm::Optional<std::string> searchLinkerScript(StringRef Path);
+llvm::Optional<std::string> searchScript(StringRef Path);
 llvm::Optional<std::string> searchLibrary(StringRef Path);
 
 } // namespace elf
 } // namespace lld
 
 #endif

ELF/Driver.cpp

void LinkerDriver::readConfigs(opt::InputArgList &Args) {
   // If --export-dynamic-symbol=foo is given and symbol foo is defined in
   // an object file in an archive file, that object file should be pulled
   // out and linked. (It doesn't have to behave like that from technical
   // point of view, but this is needed for compatibility with GNU.)
   for (auto *Arg : Args.filtered(OPT_export_dynamic_symbol))
     Config->Undefined.push_back(Arg->getValue());
 
   for (auto *Arg : Args.filtered(OPT_version_script))
-    if (Optional<MemoryBufferRef> Buffer = readFile(Arg->getValue()))
+    if (Optional<std::string> Path = searchScript(Arg->getValue())) {
+      if (Optional<MemoryBufferRef> Buffer = readFile(*Path))
         readVersionScript(*Buffer);
+    } else {
+      error(Twine("cannot find version script ") + Arg->getValue());
+    }
 }
 
 // Some Config members do not directly correspond to any particular
 // command line options, but computed based on other Config values.
 // This function initialize such members. See Config.h for the details
 // of these values.
 static void setConfigs(opt::InputArgList &Args) {
   ELFKind Kind = Config->EKind;
for (auto *Arg : Args) {
     case OPT_defsym: {
       StringRef From;
       StringRef To;
       std::tie(From, To) = StringRef(Arg->getValue()).split('=');
       readDefsym(From, MemoryBufferRef(To, "-defsym"));
       break;
     }
     case OPT_script:
-      if (Optional<std::string> Path = searchLinkerScript(Arg->getValue())) {
+      if (Optional<std::string> Path = searchScript(Arg->getValue())) {
         if (Optional<MemoryBufferRef> MB = readFile(*Path))
           readLinkerScript(*MB);
         break;
       }
       error(Twine("cannot find linker script ") + Arg->getValue());
       break;
     case OPT_as_needed:
       Config->AsNeeded = true;

ELF/DriverUtils.cpp

if (!Config->Static)
       if (Optional<std::string> S = findFile(Dir, "lib" + Name + ".so"))
         return S;
     if (Optional<std::string> S = findFile(Dir, "lib" + Name + ".a"))
       return S;
   }
   return None;
 }
 
-// If a linker script doesn't exist in the current directory, we also look for
-// the script in the '-L' search paths. This matches the behaviour of both '-T'
-// and linker script INPUT() directives in ld.bfd.
-Optional<std::string> elf::searchLinkerScript(StringRef Name) {
+// If a linker/version script doesn't exist in the current directory, we also
+// look for the script in the '-L' search paths. This matches the behaviour of
+// '-T', --version-script=, and linker script INPUT() command in ld.bfd.
+Optional<std::string> elf::searchScript(StringRef Name) {
   if (fs::exists(Name))
     return Name.str();
   return findFromSearchPaths(Name);
 }

ELF/ScriptParser.cpp

 void ScriptParser::readInclude() {
   StringRef Tok = unquote(next());
 
   if (!Seen.insert(Tok).second) {
     setError("there is a cycle in linker script INCLUDEs");
     return;
   }
 
-  if (Optional<std::string> Path = searchLinkerScript(Tok)) {
+  if (Optional<std::string> Path = searchScript(Tok)) {
     if (Optional<MemoryBufferRef> MB = readFile(*Path))
       tokenize(*MB);
     return;
   }
   setError("cannot find linker script " + Tok);
 }
 
 void ScriptParser::readInput() {

test/ELF/version-script-in-search-path.s

+# REQUIRES: x86
+# Check that we fall back to search paths if a version script was not found
+# This behaviour matches ld.bfd.
+
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t.o
+# RUN: mkdir -p %T/searchpath
+# RUN: echo '{};' > %T/searchpath/t.script
+# RUN: ld.lld -L%T/searchpath --version-script=t.script %t.o -o /dev/null
+# RUN: not ld.lld --version-script=t.script %t.o 2>&1 | FileCheck -check-prefix ERROR %s
+# ERROR: error: cannot find version script