diff --git a/driver/Makefile.in b/driver/Makefile.in
index 9a8ded7dd..224396532 100644
--- a/driver/Makefile.in
+++ b/driver/Makefile.in
@@ -79,7 +79,7 @@ dep:
 	mv $*.d dep
 
 main.o: main.c globals.h ../version_base.h ../version_tag.h Makefile
-	$(CC) $(CPPFLAGS) $(CFLAGS) -MD -c -DIVL_ROOT='"@libdir@/ivl$(suffix)"'  -DIVL_INC='"@includedir@"' -DIVL_LIB='"@libdir@"' -DDLLIB='"@DLLIB@"' $(srcdir)/main.c
+	$(CC) $(CPPFLAGS) $(CFLAGS) -MD -c -DIVL_ROOT='"@libdir@/ivl$(suffix)"'  -DIVL_SUFFIX='"$(suffix)"' -DIVL_INC='"@includedir@"' -DIVL_LIB='"@libdir@"' -DDLLIB='"@DLLIB@"' $(srcdir)/main.c
 	mv $*.d dep
 
 cflexor.o: cflexor.c cfparse.h
diff --git a/driver/main.c b/driver/main.c
index 1cf94da1a..c47149b8f 100644
--- a/driver/main.c
+++ b/driver/main.c
@@ -760,25 +760,23 @@ int main(int argc, char **argv)
       int opt, idx;
 
 #ifdef __MINGW32__
-      { char * s;
-	char basepath[1024], tmp[1024];
+	/* Calculate the ivl_root from the path to the command. This
+	   is necessary because of the installation process on
+	   Windows. Mostly, it is those darn drive letters, but oh
+	   well. We know the command path is formed like this:
+
+		D:\iverilog\bin\iverilog.exe
+
+	   The module path in a Windows installation is the path:
+
+		D:\iverilog\lib\ivl$(suffix)
+
+	   so we chop the file name and the last directory by
+	   turning the last two \ characters to null. Then we append
+	   the lib\ivl$(suffix) to finish. */
+      { char *s;
+	char basepath[4096], tmp[4096];
 	GetModuleFileName(NULL, tmp, sizeof tmp);
-
-	  /* Calculate the ivl_root from the path to the command. This
-	     is necessary because of the installation process in
-	     Windows. Mostly, it is those darn drive letters, but oh
-	     well. We know the command path is formed like this:
-
-	         D:\iverilog\bin\iverilog.exe
-
-	     The IVL_ROOT in a Windows installation is the path:
-
-	         D:\iverilog\lib\ivl
-
-	     so we chop the file name and the last directory by
-	     turning the last two \ characters to null. Then we append
-	     the lib\ivl to finish. */
-
 	  /* Convert to a short name to remove any embedded spaces. */
 	GetShortPathName(tmp, basepath, sizeof basepath);
 	strncpy(ivl_root, basepath, MAXSIZE);
@@ -786,7 +784,7 @@ int main(int argc, char **argv)
 	if (s) *s = 0;
 	s = strrchr(ivl_root, sep);
 	if (s) *s = 0;
-	strcat(ivl_root, "\\lib\\ivl");
+	strcat(ivl_root, "\\lib\\ivl" IVL_SUFFIX);
 
 	base = ivl_root;
       }
diff --git a/vvp/Makefile.in b/vvp/Makefile.in
index b17380602..7ca3b2fa8 100644
--- a/vvp/Makefile.in
+++ b/vvp/Makefile.in
@@ -53,7 +53,7 @@ LIBS = @LIBS@ @EXTRALIBS@
 
 dllib=@DLLIB@
 
-MDIR1 = -DMODULE_DIR1=\"$(libdir)/ivl$(suffix)/.\"
+MDIR1 = -DMODULE_DIR1='"$(libdir)/ivl$(suffix)"'
 
 all: dep vvp@EXEEXT@ libvpi.a vvp.man
 
@@ -105,7 +105,7 @@ dep:
 	mkdir dep
 
 %.o: %.cc config.h
-	$(CXX) $(CPPFLAGS) $(MDIR1) $(MDIR2) $(CXXFLAGS) -MD -c $< -o $*.o
+	$(CXX) $(CPPFLAGS) -DIVL_SUFFIX='"$(suffix)"' $(MDIR1) $(MDIR2) $(CXXFLAGS) -MD -c $< -o $*.o
 	mv $*.d dep/$*.d
 
 %.o: %.c config.h
diff --git a/vvp/main.cc b/vvp/main.cc
index 3e9785b8d..7f6fbc700 100644
--- a/vvp/main.cc
+++ b/vvp/main.cc
@@ -211,16 +211,31 @@ int main(int argc, char*argv[])
       extern int  stop_is_finish_exit_code;
 
 #ifdef __MINGW32__
-	/* In the Windows world, we get the first module path
-	   component relative the location where the binary lives. */
-      { char path[4096], *s;
-        GetModuleFileName(NULL,path,1024);
-	  /* Get to the end.  Search back twice for backslashes */
-	s = path + strlen(path);
-	while (*s != '\\') s--; s--;
-	while (*s != '\\') s--;
-	strcpy(s,"\\lib\\ivl");
-	vpip_module_path[0] = strdup(path);
+	/* Calculate the module path from the path to the command.
+	   This is necessary because of the installation process on
+	   Windows. Mostly, it is those darn drive letters, but oh
+	   well. We know the command path is formed like this:
+
+		D:\iverilog\bin\iverilog.exe
+
+	   The IVL_ROOT in a Windows installation is the path:
+
+		D:\iverilog\lib\ivl$(suffix)
+
+	   so we chop the file name and the last directory by
+	   turning the last two \ characters to null. Then we append
+	   the lib\ivl$(suffix) to finish. */
+      { char *s;
+	char basepath[4096], tmp[4096];
+	GetModuleFileName(NULL, tmp, sizeof tmp);
+	  /* Convert to a short na,e to remove any embedded spaces. */
+	GetShortPathName(tmp, basepath, sizeof basepath);
+	s = strrchr(basepath, '\\');
+	if (s) *s = 0;
+	s = strrchr(basepath, '\\');
+	if (s) *s = 0;
+	strcat(s, "\\lib\\ivl" IVL_SUFFIX);
+	vpip_module_path[0] = strdup(basepath);
       }
 #endif