Index: lld/COFF/Driver.cpp
===================================================================
--- lld/COFF/Driver.cpp
+++ lld/COFF/Driver.cpp
@@ -56,7 +56,7 @@
 LinkerDriver *Driver;
 
 bool link(ArrayRef<const char *> Args, bool CanExitEarly, raw_ostream &Diag) {
-  errorHandler().LogName = Args[0];
+  errorHandler().LogName = sys::path::filename(Args[0]);
   errorHandler().ErrorOS = &Diag;
   errorHandler().ColorDiagnostics = Diag.has_colors();
   errorHandler().ErrorLimitExceededMsg =
Index: lld/COFF/InputFiles.cpp
===================================================================
--- lld/COFF/InputFiles.cpp
+++ lld/COFF/InputFiles.cpp
@@ -27,6 +27,7 @@
 #include "llvm/Support/Error.h"
 #include "llvm/Support/ErrorOr.h"
 #include "llvm/Support/FileSystem.h"
+#include "llvm/Support/Path.h"
 #include "llvm/Target/TargetOptions.h"
 #include <cstring>
 #include <system_error>
@@ -488,10 +489,7 @@
 
 // Returns the last element of a path, which is supposed to be a filename.
 static StringRef getBasename(StringRef Path) {
-  size_t Pos = Path.find_last_of("\\/");
-  if (Pos == StringRef::npos)
-    return Path;
-  return Path.substr(Pos + 1);
+  return sys::path::filename(Path, sys::path::Style::windows);
 }
 
 // Returns a string in the format of "foo.obj" or "foo.obj(bar.lib)".
Index: lld/ELF/Driver.cpp
===================================================================
--- lld/ELF/Driver.cpp
+++ lld/ELF/Driver.cpp
@@ -73,7 +73,7 @@
 
 bool elf::link(ArrayRef<const char *> Args, bool CanExitEarly,
                raw_ostream &Error) {
-  errorHandler().LogName = Args[0];
+  errorHandler().LogName = sys::path::filename(Args[0]);
   errorHandler().ErrorLimitExceededMsg =
       "too many errors emitted, stopping now (use "
       "-error-limit=0 to see all errors)";
Index: lld/lib/Driver/DarwinLdDriver.cpp
===================================================================
--- lld/lib/Driver/DarwinLdDriver.cpp
+++ lld/lib/Driver/DarwinLdDriver.cpp
@@ -1143,7 +1143,7 @@
 /// This is where the link is actually performed.
 bool link(llvm::ArrayRef<const char *> args, bool CanExitEarly,
           raw_ostream &Error) {
-  errorHandler().LogName = args[0];
+  errorHandler().LogName = llvm::sys::path::filename(args[0]);
   errorHandler().ErrorLimitExceededMsg =
       "too many errors emitted, stopping now (use "
       "'-error-limit 0' to see all errors)";
Index: lld/wasm/Driver.cpp
===================================================================
--- lld/wasm/Driver.cpp
+++ lld/wasm/Driver.cpp
@@ -74,7 +74,7 @@
 
 bool lld::wasm::link(ArrayRef<const char *> Args, bool CanExitEarly,
                      raw_ostream &Error) {
-  errorHandler().LogName = Args[0];
+  errorHandler().LogName = sys::path::filename(Args[0]);
   errorHandler().ErrorOS = &Error;
   errorHandler().ColorDiagnostics = Error.has_colors();
   errorHandler().ErrorLimitExceededMsg =