[lld] Check errors from expanding response files

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".

Differental revision: https://reviews.llvm.org/D137477

2 files changed, 9 insertions, 1 deletions

diff --git a/lld/test/ELF/basic.s b/lld/test/ELF/basic.s
index 33c01944b7c1..587fd1641500 100644
--- a/lld/test/ELF/basic.s
+++ b/lld/test/ELF/basic.s
@@ -218,6 +218,12 @@ _start:
 # 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]]
diff --git a/lld/tools/lld/lld.cpp b/lld/tools/lld/lld.cpp
index b0e28d15fa29..700c0b770e20 100644
--- a/lld/tools/lld/lld.cpp
+++ b/lld/tools/lld/lld.cpp
@@ -89,7 +89,9 @@ static bool isPETarget(std::vector<const char *> &v) {
   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;