Handle extra info in dylink section (#4112)

If extra data is found in this section simply propagate it.

Also, remove some dead code from wasm-binary.cpp.

3 files changed, 17 insertions, 0 deletions

diff --git a/test/lit/binary/dylink.test b/test/lit/binary/dylink.test
new file mode 100644
index 000000000..72341c9ba
--- /dev/null
+++ b/test/lit/binary/dylink.test
@@ -0,0 +1,15 @@
+# Verify that extra bytes in the dylink section are preserved.
+#
+# `dylink.test.wasm` was generated using emscripten to build a side
+# module with two TLS exports (which adds extra information to the
+# dylink section) using:
+#  `emcc -s SIDE_MODULE side.c`
+#
+# side.c:
+#   _Thread_local int foo = 10;
+#   _Thread_local int bar = 11;
+#
+# and then removing all sections except the dylink section using:
+#  `llvm-objcopy --only-section=dylink`
+RUN: wasm-opt -O1 %s.wasm -o %t.o
+RUN: cmp %s.wasm %t.o
diff --git a/test/lit/binary/dylink.test.wasm b/test/lit/binary/dylink.test.wasm
new file mode 100755
index 000000000..401028d96
--- /dev/null
+++ b/test/lit/binary/dylink.test.wasm
diff --git a/test/lit/lit.cfg.py b/test/lit/lit.cfg.py
index 23b0c3de6..ac89a5991 100644
--- a/test/lit/lit.cfg.py
+++ b/test/lit/lit.cfg.py
@@ -10,6 +10,8 @@ config.test_exec_root = os.path.join(config.binaryen_build_root, 'test')
 
 # Replace all Binaryen tools with their absolute paths
 bin_dir = os.path.join(config.binaryen_build_root, 'bin')
+assert(os.path.isdir(bin_dir))
+
 for tool_file in os.listdir(bin_dir):
     tool_path = config.binaryen_build_root + '/bin/' + tool_file
     tool = tool_file[:-4] if tool_file.endswith('.exe') else tool_file