diff --git a/src/core/platform.h b/src/core/platform.h
index 2fe64a9..ecb25b9 100644
--- a/src/core/platform.h
+++ b/src/core/platform.h
@@ -449,6 +449,7 @@
 #    define SUPPORTS_NETWORKING (HAVE_SOCKET && !IS_SORTIX && !IS_DOS_DJGPP && !IS_REDOX)
 #    define SUPPORTS_SYSLOG (HAVE_SYSLOG && !IS_SKYOS && !IS_RISCOS)
 #    define NEEDS_SWAB_IMPL (IS_CYGWIN || IS_SYLLABLE || IS_ANDROID || IS_SORTIX)
+#    define SWAB_TAKES_CHAR_PTRS (IS_MINGW)
 #    define USES_MBLEN (!IS_ANDROID && !IS_AROS)
 #    define USES_DOS_DEVICE_PATH (IS_DOS_DJGPP || (IS_WIN32 && !IS_CYGWIN) || (IS_OS2 && !IS_EMX))
 #    define USES_DEVICE_PATH (IS_AROS || IS_RISCOS || IS_REDOX || USES_DOS_DEVICE_PATH)
@@ -503,13 +504,6 @@
 #   define UNAME_SUCCESS_ZERO 1
 #endif  
 
-// Work around single-arg mkdir on MinGW.
-// consider using autoconf AX_FUNC_MKDIR if
-// we need to handle any more cases here
-/*#if IS_MINGW
-#   define mkdir(a,b) mkdir(a)
-#endif*/
-
 //=============================================================================
 // Miscellaneous
 //
diff --git a/src/core/tw_signal.cpp b/src/core/tw_signal.cpp
index 67f3d9e..916f3d9 100644
--- a/src/core/tw_signal.cpp
+++ b/src/core/tw_signal.cpp
@@ -83,7 +83,7 @@ void util_SignalHandler(int sig)
 
 void tw_psignal(int sig, const TCHAR* str)
 {
-    const TCHAR* siglist[NSIG] = {_T("Unknown Signal"),
+    const TCHAR* siglist[] =    { _T("Unknown Signal"),
                                   _T("Hangup"),
                                   _T("Interrupt"),
                                   _T("Quit"),
diff --git a/src/fco/signature.cpp b/src/fco/signature.cpp
index ade3950..c0e5b5f 100644
--- a/src/fco/signature.cpp
+++ b/src/fco/signature.cpp
@@ -114,8 +114,8 @@ void cArchiveSigGen::CalculateSignatures(cArchive& a)
 
     if (s_direct)
     {
-        unsigned long mod    = (unsigned long)abBuf % iSignature::SUGGESTED_BLOCK_SIZE;
-        unsigned long offset = (iSignature::SUGGESTED_BLOCK_SIZE - mod);
+        uintptr_t mod    = (uintptr_t)abBuf % iSignature::SUGGESTED_BLOCK_SIZE;
+        uintptr_t offset = (iSignature::SUGGESTED_BLOCK_SIZE - mod);
         pBuf                 = abBuf + offset;
     }
 
diff --git a/src/twadmin/twadmincl.cpp b/src/twadmin/twadmincl.cpp
index 2c4e197..ae03c4a 100644
--- a/src/twadmin/twadmincl.cpp
+++ b/src/twadmin/twadmincl.cpp
@@ -2076,8 +2076,15 @@ static bool ChangePassphrase(const TCHAR* keyPath, wc16_string passphraseOld, wc
     memcpy(passphraseCopyOld, passphraseOld.data(), passphraseLenOld);
     memcpy(passphraseCopy, passphrase.data(), passphraseLen);
 #else
+
+ #if SWAB_TAKES_CHAR_PTRS   
+    swab((char*)passphraseOld.data(), (char*)passphraseCopyOld, passphraseLenOld);
+    swab((char*)passphrase.data(), (char*)passphraseCopy, passphraseLen);
+#else
     swab(passphraseOld.data(), passphraseCopyOld, passphraseLenOld);
     swab(passphrase.data(), passphraseCopy, passphraseLen);
+#endif
+    
 #endif
 
     bool result;
diff --git a/src/twtest/test.cpp b/src/twtest/test.cpp
index ebfbef5..e12b928 100644
--- a/src/twtest/test.cpp
+++ b/src/twtest/test.cpp
@@ -385,7 +385,7 @@ std::string TwTestDir()
         iFSServices::GetInstance()->GetCurrentDir(dir);
         dir.append("/TWTestData");
         TCERR << "Using test directory: " << dir << std::endl;
-        mkdir(dir.c_str(), 0777);
+        tw_mkdir(dir.c_str(), 0777);
     }
 
     return dir;
diff --git a/src/twtest/test.h b/src/twtest/test.h
index dfef413..67de908 100644
--- a/src/twtest/test.h
+++ b/src/twtest/test.h
@@ -92,5 +92,16 @@ void RegisterTest(const std::string& suite, const std::string testName, TestPtr
 void skip(const std::string& reason);
 void fail(const std::string& reason);
 
+////////////////////////////////////////////////////////////////////////////
+
+// Misc platform utility stuff available for all tests
+
+// Could use AX_FUNC_MKDIR autoconf macro if we need to handle
+// any additional cases besides these
+#if IS_MINGW
+#    define tw_mkdir(a,b) mkdir(a)
+#else
+#    define tw_mkdir(a,b) mkdir(a,b)
+#endif
 
 #endif // __TEST_H
diff --git a/src/twtest/textreportviewer_t.cpp b/src/twtest/textreportviewer_t.cpp
index ed7d452..9567f1f 100644
--- a/src/twtest/textreportviewer_t.cpp
+++ b/src/twtest/textreportviewer_t.cpp
@@ -151,9 +151,9 @@ void TestTextReportViewer()
         fcoNameSpec1 = fcoNameTempDir += _T("SPEC1/");
         fcoNameSpec2 = fcoNameTempDir += _T("SPEC2/");
         
-        mkdir( fcoNameTempDir.c_str(), 0777 );
-        mkdir( fcoNameSpec1.AsString().c_str(), 0777 );
-        mkdir( fcoNameSpec2.AsString().c_str(), 0777 );
+        tw_mkdir( fcoNameTempDir.c_str(), 0777 );
+        tw_mkdir( fcoNameSpec1.AsString().c_str(), 0777 );
+        tw_mkdir( fcoNameSpec2.AsString().c_str(), 0777 );
         
         fcoNameTempFile = fcoNameTempDir += _T("twtempXXXXXX");
         pFSServices->MakeTempFilename( fcoNameTempFile );
@@ -473,7 +473,7 @@ void MakeFile(TSTRING& strNameMakeMe)
 
 void MakeDir(const TCHAR* const lpszDirName)
 {
-    TEST(0 == mkdir(lpszDirName, 0777))
+    TEST(0 == tw_mkdir(lpszDirName, 0777))
 }
 
 //#endif //FIXED_TRV_TEST_SUITE
diff --git a/src/twtest/twutil_t.cpp b/src/twtest/twutil_t.cpp
index aaa4ebc..7b0211d 100644
--- a/src/twtest/twutil_t.cpp
+++ b/src/twtest/twutil_t.cpp
@@ -62,7 +62,7 @@ void TestTWUtil()
     TSTRING tmpFN  = TwTestPath("fileexiststest.tmp");
 
     // make a subdir in the TEMP_DIR
-    mkdir(tmpDir.c_str(), 0700);
+    tw_mkdir(tmpDir.c_str(), 0700);
     chmod(tmpDir.c_str(), 0700);
 
     // make sure file is not there