1 files changed, 28 insertions, 2 deletions
diff --git a/src/support/command-line.cpp b/src/support/command-line.cpp
index 23ded0346..2b1b0b10b 100644
--- a/src/support/command-line.cpp
+++ b/src/support/command-line.cpp
@@ -17,6 +17,15 @@
 #include "support/command-line.h"
 #include "config.h"
 #include "support/debug.h"
+#include "support/path.h"
+
+#ifdef USE_WSTRING_PATHS
+#ifndef NOMINMAX
+#define NOMINMAX
+#endif
+#include "windows.h"
+#include "shellapi.h"
+#endif
 
 using namespace wasm;
 
@@ -163,6 +172,23 @@ Options& Options::add_positional(const std::string& name,
 }
 
 void Options::parse(int argc, const char* argv[]) {
+
+// On Windows, get the wide char version of the command line flags, and convert
+// each one to std::string with UTF-8 manually. This means that all paths in
+// Binaryen are stored this way on all platforms right up until a library call
+// is made to open a file (at which point we use Path::to_path to convert back)
+// so that it works with the underlying Win32 APIs.
+// Only argList (and not argv) should be used below.
+#ifdef USE_WSTRING_PATHS
+  LPWSTR* argListW = CommandLineToArgvW(GetCommandLineW(), &argc);
+  std::vector<std::string> argList;
+  for (size_t i = 0, e = argc; i < e; ++i) {
+    argList.push_back(wasm::Path::wstring_to_string(argListW[i]));
+  }
+#else
+  const char** argList = argv;
+#endif
+
   assert(argc > 0 && "expect at least program name as an argument");
   size_t positionalsSeen = 0;
   auto dashes = [](const std::string& s) {
@@ -174,7 +200,7 @@ void Options::parse(int argc, const char* argv[]) {
     return s.size();
   };
   for (size_t i = 1, e = argc; i != e; ++i) {
-    std::string currentOption = argv[i];
+    std::string currentOption = argList[i];
 
     // "-" alone is a positional option
     if (dashes(currentOption) == 0 || currentOption == "-") {
@@ -241,7 +267,7 @@ void Options::parse(int argc, const char* argv[]) {
                       << currentOption << "'\n";
             exit(EXIT_FAILURE);
           }
-          argument = argv[++i];
+          argument = argList[++i];
         }
         break;
       case Arguments::Optional: