[lld] Check errors from expanding response files

[hans]

Summary

Previously the response file expansion code would print the error, but lld would not exit, which was odd.

lld does response file expansion in the different drivers, but it's also done in main() first, so it's enough to check there.

By checking for these errors we would have caught when D136090 introduced a bug that made lld print errors for response files which contained "-rpath @foo".

[sepavloff]

LGTM.

[MaskRay]

LGTM.

lld/test/ELF/basic.s

221

For newer tests we use ## for non-RUN non-CHECK comments.

224

[thakis]

Thanks!

[hans]

hans mentioned this in rG19a7939404a3: [lld] Check errors from expanding response files.

That was the commit. Seems I failed to spell "Differential" correctly.

lld/test/ELF/basic.s

 # RUN:   %s --check-prefix=WINRSP
 # WINRSP: cannot open c:\blah\foo
 
 # Test for the response file (invalid quoting style)
 # RUN: not ld.lld --rsp-quoting=patatino %t 2>&1 | FileCheck %s \
 # RUN:   --check-prefix=INVRSP
 # INVRSP: invalid response file quoting: patatino
 
+# Test erroring on a recursive response file, but only once.
+# RUN: echo @%t.responsefile > %t.responsefile
+# RUN: not ld.lld %t @%t.responsefile 2>&1 | FileCheck %s --check-prefix=RECRSP
+# RECRSP: recursive expansion of: '{{.*}}.responsefile'
+# RECRSP-NOT: recursive expansion of
+
 # RUN: not ld.lld %t.foo -o /dev/null 2>&1 | \
 # RUN:  FileCheck -DMSG=%errc_ENOENT --check-prefix=MISSING %s
 # MISSING: cannot open {{.*}}.foo: [[MSG]]
 
 # RUN: not ld.lld -o /dev/null 2>&1 | \
 # RUN:  FileCheck --check-prefix=NO_INPUT %s
 # NO_INPUT: ld.lld{{.*}}: no input files
 

lld/tools/lld/lld.cpp

if (StringRef(*it) != "-m")
       continue;
     return isPETargetName(*(it + 1));
   }
   // Expand response files (arguments in the form of @<filename>)
   // to allow detecting the -m argument from arguments in them.
   SmallVector<const char *, 256> expandedArgs(v.data(), v.data() + v.size());
   BumpPtrAllocator a;
   StringSaver saver(a);
-  cl::ExpandResponseFiles(saver, getDefaultQuotingStyle(), expandedArgs);
+  cl::ExpansionContext ECtx(saver.getAllocator(), getDefaultQuotingStyle());
+  if (Error Err = ECtx.expandResponseFiles(expandedArgs))
+    die(toString(std::move(Err)));
   for (auto it = expandedArgs.begin(); it + 1 != expandedArgs.end(); ++it) {
     if (StringRef(*it) != "-m")
       continue;
     return isPETargetName(*(it + 1));
   }
 
 #ifdef LLD_DEFAULT_LD_LLD_IS_MINGW
   return true;