diff --git a/src/mred/Makefile.in b/src/mred/Makefile.in
index a167e57228..58cce92636 100644
--- a/src/mred/Makefile.in
+++ b/src/mred/Makefile.in
@@ -239,8 +239,7 @@ install-lib:
 	cd ..; $(ICP) mred/libmred.@LIBSFX@ "$(libdir)"
 
 install_wx_xt:
-	cd ..; if [ ! -d "$(bindir)" ] ; then mkdir "$(bindir)" ; fi
-	cd ..; rm -f "$(bindir)/mred"
+	cd ..; mkdir -p "$(bindir)"; rm -f "$(bindir)/mred"
 	$(MAKE) @MRLIBINSTALL@
 	cd ..; $(ICP) mred/mred "$(bindir)"
 	$(MZSCHEME) -mvqu "$(srcdir)/../mzscheme/collects-path.ss" "$(prefix)/bin/mred@EXE_SUFFIX@" @COLLECTS_PATH@
@@ -255,10 +254,7 @@ install_wx_mac:
 	rm -f $(MRFWDIR)/PLT_MrEd
 	rm -rf $(MRFWDIR)/Resources
 	if [ @FRAMEWORK_REL_INSTALL@ = yes ] ; then rm -rf $(MRFWDIR) ; fi
-	if [ ! -d @FRAMEWORK_INSTALL_DIR@ ] ; then mkdir @FRAMEWORK_INSTALL_DIR@ ; fi
-	if [ ! -d $(MRFWDIR) ] ; then mkdir $(MRFWDIR) ; fi
-	if [ ! -d $(MRFWDIR)/Versions ] ; then mkdir $(MRFWDIR)/Versions ; fi
-	if [ ! -d $(MRFWDIR)/Versions/$(FWVERSION) ] ; then mkdir $(MRFWDIR)/Versions/$(FWVERSION) ; fi
+	mkdir -p @FRAMEWORK_INSTALL_DIR@ "$(MRFWDIR)/Versions/$(FWVERSION)"
 	cd ..; rm -rf $(collectsdir)/launcher/Starter.app
 	cd ..; rm -rf $(prefix)/MrEd.app
 	cd ..; $(ICP) -r mred/MrEd.app $(prefix)/.
@@ -266,8 +262,7 @@ install_wx_mac:
 	$(ICP) -r PLT_MrEd.framework/Versions/$(FWVERSION)/Resources $(MRFWDIR)/Versions/$(FWVERSION)/Resources
 	ln -s Versions/$(FWVERSION)/PLT_MrEd $(MRFWDIR)/
 	ln -s Versions/$(FWVERSION)/Resources $(MRFWDIR)/
-	if [ ! -d $(collectsdir) ] ; then mkdir $(collectsdir) ; fi
-	if [ ! -d $(collectsdir)/launcher ] ; then mkdir $(collectsdir)/launcher ; fi
+	mkdir -p $(collectsdir)/launcher
 	cd ..; $(ICP) -r mred/Starter.app $(collectsdir)/launcher/.
 	if [ @FRAMEWORK_REL_INSTALL@ = yes ] ; then /usr/bin/install_name_tool -change "@executable_path/../../../PLT_MrEd.framework/Versions/$(FWVERSION)/PLT_MrEd" "@executable_path/../../../lib/PLT_MrEd.framework/Versions/$(FWVERSION)/PLT_MrEd" "$(prefix)/MrEd.app/Contents/MacOS/MrEd" ; fi
 	$(MZSCHEME) -mvqu "$(srcdir)/../mzscheme/collects-path.ss" "$(prefix)/MrEd.app/Contents/MacOS/MrEd" ../../../collects
@@ -298,19 +293,18 @@ install-3m_wx_xt:
 	$(MAKE) @MRLIBINSTALL@3m
 
 install-3m_wx_mac:
-	rm -f $(MRFWDIR)/Versions/$(FWVERSION)_3m/PLT_MrEd
-	rm -rf $(MRFWDIR)/Versions/$(FWVERSION)_3m/Resources
-	if [ ! -d $(MRFWDIR)/Versions/$(FWVERSION)_3m ] ; then mkdir $(MRFWDIR)/Versions/$(FWVERSION)_3m ; fi
-	cd ..; rm -rf $(collectsdir)/launcher/Starter3m.app
-	cd ..; rm -rf $(prefix)/MrEd3m.app
-	cd ..; $(ICP) -r mred/MrEd3m.app $(prefix)/.
-	$(ICP) PLT_MrEd.framework/Versions/$(FWVERSION)_3m/PLT_MrEd $(MRFWDIR)/Versions/$(FWVERSION)_3m/PLT_MrEd
-	$(ICP) -r PLT_MrEd.framework/Versions/$(FWVERSION)_3m/Resources $(MRFWDIR)/Versions/$(FWVERSION)_3m/Resources
-	if [ ! -d $(collectsdir) ] ; then mkdir $(collectsdir) ; fi
-	if [ ! -d $(collectsdir)/launcher ] ; then mkdir $(collectsdir)/launcher ; fi
-	cd ..; $(ICP) -r mred/Starter3m.app $(collectsdir)/launcher/.
+	rm -f "$(MRFWDIR)/Versions/$(FWVERSION)_3m/PLT_MrEd"
+	rm -rf "$(MRFWDIR)/Versions/$(FWVERSION)_3m/Resources"
+	mkdir -p "$(MRFWDIR)/Versions/$(FWVERSION)_3m"
+	cd ..; rm -rf "$(collectsdir)/launcher/Starter3m.app"
+	cd ..; rm -rf "$(prefix)/MrEd3m.app"
+	cd ..; $(ICP) -r "mred/MrEd3m.app" "$(prefix)/."
+	$(ICP) "PLT_MrEd.framework/Versions/$(FWVERSION)_3m/PLT_MrEd" "$(MRFWDIR)/Versions/$(FWVERSION)_3m/PLT_MrEd"
+	$(ICP) -r "PLT_MrEd.framework/Versions/$(FWVERSION)_3m/Resources" "$(MRFWDIR)/Versions/$(FWVERSION)_3m/Resources"
+	mkdir -p "$(collectsdir)/launcher"
+	cd ..; $(ICP) -r "mred/Starter3m.app" "$(collectsdir)/launcher/."
 	if [ @FRAMEWORK_REL_INSTALL@ = yes ] ; then /usr/bin/install_name_tool -change "@executable_path/../../../PLT_MrEd.framework/Versions/$(FWVERSION)_3m/PLT_MrEd" "@executable_path/../../../lib/PLT_MrEd.framework/Versions/$(FWVERSION)_3m/PLT_MrEd" "$(prefix)/MrEd3m.app/Contents/MacOS/MrEd3m" ; fi
-	$(MZSCHEME) -mvqu "$(srcdir)/../mzscheme/collects-path.ss" "$(prefix)/MrEd3m.app/Contents/MacOS/MrEd3m" ../../../collects
+	$(MZSCHEME) -mvqu "$(srcdir)/../mzscheme/collects-path.ss" "$(prefix)/MrEd3m.app/Contents/MacOS/MrEd3m" "../../../collects"
 
 install-3m:
 	$(MAKE) install-3m_@WXVARIANT@
diff --git a/src/mred/gc2/Makefile.in b/src/mred/gc2/Makefile.in
index b747a3a54e..ab6e867b2c 100644
--- a/src/mred/gc2/Makefile.in
+++ b/src/mred/gc2/Makefile.in
@@ -1369,11 +1369,11 @@ MRFWRES = PLT_MrEd.framework/Versions/$(FWVERSION)_3m/Resources/PLT_MrEd.rsrc
 
 ../MrEd3m.app/Contents/MacOS/MrEd3m: $(MRFWRES) $(MRFW) mrmain.@LTO@
 	$(MREDLINKER) -o ../MrEd3m.app/Contents/MacOS/MrEd3m mrmain.@LTO@ -Wl,-headerpad_max_install_names -F. -framework PLT_MrEd -framework Carbon
-	if [ ! -d ../PLT_MrEd.framework/Versions/$(FWVERSION)_3m ] ; then mkdir ../PLT_MrEd.framework/Versions/$(FWVERSION)_3m ; fi
-	cp $(MRFW) ../$(MRFW)
-	rm -rf ../PLT_MrEd.framework/Versions/$(FWVERSION)_3m/Resources
-	cp -r PLT_MrEd.framework/Versions/$(FWVERSION)_3m/Resources ../PLT_MrEd.framework/Versions/$(FWVERSION)_3m/Resources
-	/usr/bin/install_name_tool -change "PLT_MrEd.framework/Versions/$(FWVERSION)_3m/PLT_MrEd" "@executable_path/../../../PLT_MrEd.framework/Versions/$(FWVERSION)_3m/PLT_MrEd" ../MrEd3m.app/Contents/MacOS/MrEd3m
+	mkdir -p "../PLT_MrEd.framework/Versions/$(FWVERSION)_3m"
+	cp "$(MRFW)" "../$(MRFW)"
+	rm -rf "../PLT_MrEd.framework/Versions/$(FWVERSION)_3m/Resources"
+	cp -r "PLT_MrEd.framework/Versions/$(FWVERSION)_3m/Resources" "../PLT_MrEd.framework/Versions/$(FWVERSION)_3m/Resources"
+	/usr/bin/install_name_tool -change "PLT_MrEd.framework/Versions/$(FWVERSION)_3m/PLT_MrEd" "@executable_path/../../../PLT_MrEd.framework/Versions/$(FWVERSION)_3m/PLT_MrEd" "../MrEd3m.app/Contents/MacOS/MrEd3m"
 
 $(MRFW) : $(XOBJS) $(@WXVARIANT@_PLAIN_OBJS) ../../mzscheme/libmzscheme3m.@LIBSFX@
 	$(MREDLINKER) -dynamiclib -o $(MRFW) -Wl,-headerpad_max_install_names $(XOBJS) $(@WXVARIANT@_PLAIN_OBJS) ../../mzscheme/libmzscheme3m.@LIBSFX@ $(@WXVARIANT@_LIBS) @X_EXTRA_LIBS@
diff --git a/src/mzscheme/Makefile.in b/src/mzscheme/Makefile.in
index 568559819a..cb19523d63 100644
--- a/src/mzscheme/Makefile.in
+++ b/src/mzscheme/Makefile.in
@@ -155,9 +155,7 @@ mzscheme.exe: main.o libmzgcxxxxxxx.dll libmzschxxxxxxx.dll
 MZFW = PLT_MzScheme.framework/Versions/$(FWVERSION)/PLT_MzScheme
 
 $(MZFW): libmzscheme.@LIBSFX@ libmzgc.@LIBSFX@ $(SPECIALIZINGOBJECTS)
-	if [ ! -d PLT_MzScheme.framework ] ; then mkdir PLT_MzScheme.framework ; fi
-	if [ ! -d PLT_MzScheme.framework/Versions ] ; then mkdir PLT_MzScheme.framework/Versions ; fi
-	if [ ! -d PLT_MzScheme.framework/Versions/$(FWVERSION) ] ; then mkdir PLT_MzScheme.framework/Versions/$(FWVERSION) ; fi
+	mkdir -p  PLT_MzScheme.framework/Versions/$(FWVERSION)
 	$(CC) -o $(MZFW) -framework CoreFoundation -dynamiclib -all_load $(SPECIALIZINGOBJECTS) libmzscheme.@LIBSFX@ libmzgc.@LIBSFX@ @LDFLAGS@ @LIBS@
 	rm -f PLT_MzScheme.framework/PLT_MzScheme
 	ln -s Versions/$(FWVERSION)/PLT_MzScheme PLT_MzScheme.framework/PLT_MzScheme
@@ -312,10 +310,7 @@ osx-install:
 	rm -f $(MZFWDIR)/Versions/$(FWVERSION)/PLT_MzScheme
 	rm -f $(MZFWDIR)/PLT_MzScheme
 	if [ @FRAMEWORK_REL_INSTALL@ = yes ] ; then rm -rf $(MZFWDIR) ; fi
-	if [ ! -d @FRAMEWORK_INSTALL_DIR@ ] ; then mkdir @FRAMEWORK_INSTALL_DIR@ ; fi
-	if [ ! -d $(MZFWDIR) ] ; then mkdir $(MZFWDIR) ; fi
-	if [ ! -d $(MZFWDIR)/Versions ] ; then mkdir $(MZFWDIR)/Versions ; fi
-	if [ ! -d $(MZFWDIR)/Versions/$(FWVERSION) ] ; then mkdir $(MZFWDIR)/Versions/$(FWVERSION) ; fi
+	mkdir -p @FRAMEWORK_INSTALL_DIR@ "$(MZFWDIR)/Versions/$(FWVERSION)"
 	cp $(MZFW) $(MZFWDIR)/Versions/$(FWVERSION)/
 	ln -s Versions/$(FWVERSION)/PLT_MzScheme $(MZFWDIR)/
 	if [ @FRAMEWORK_REL_INSTALL@ = yes ] ; then /usr/bin/install_name_tool -change "@executable_path/PLT_MzScheme.framework/Versions/$(FWVERSION)/PLT_MzScheme" "@executable_path/../lib/PLT_MzScheme.framework/Versions/$(FWVERSION)/PLT_MzScheme" "$(bindir)/mzscheme" ; fi
@@ -325,13 +320,13 @@ MZFWMMM = PLT_MzScheme.framework/Versions/$(FWVERSION)_3m/PLT_MzScheme
 install-3m@OSX@:
 	$(MAKE) install-3m-basic
 	rm -f $(MZFWDIR)/Versions/$(FWVERSION)_3m/PLT_MzScheme
-	if [ ! -d $(MZFWDIR)/Versions/$(FWVERSION)_3m ] ; then mkdir $(MZFWDIR)/Versions/$(FWVERSION)_3m ; fi
+	mkdir -p "$(MZFWDIR)/Versions/$(FWVERSION)_3m"
 	cp $(MZFWMMM) $(MZFWDIR)/Versions/$(FWVERSION)_3m/
 	if [ @FRAMEWORK_REL_INSTALL@ = yes ] ; then /usr/bin/install_name_tool -change "@executable_path/PLT_MzScheme.framework/Versions/$(FWVERSION)_3m/PLT_MzScheme" "@executable_path/../lib/PLT_MzScheme.framework/Versions/$(FWVERSION)_3m/PLT_MzScheme" "$(bindir)/mzscheme3m" ; fi
 
 unix-cygwin-install:
 	$(MAKE) unix-install
-	cd dynsrc; $(MAKE) cygwin-install	
+	cd dynsrc; $(MAKE) cygwin-install
 
 config:
 	autoconf $(srcdir)/configure.ac | mzscheme -qr $(srcdir)/clean_ac.ss > $(srcdir)/../configure
diff --git a/src/mzscheme/dynsrc/Makefile.in b/src/mzscheme/dynsrc/Makefile.in
index 698c80ab41..2602db0526 100644
--- a/src/mzscheme/dynsrc/Makefile.in
+++ b/src/mzscheme/dynsrc/Makefile.in
@@ -63,8 +63,7 @@ cygwin-install:
 	dlltool --def mzdynx.def --output-exp mzdyn.exp
 	dlltool --input-def $(srcdir)/../include/mzwin.def --output-lib libmzschxxxxxxx.lib --dllname libmzschxxxxxxx.dll
 	dlltool --input-def $(srcdir)/../include/gmzwin.def --output-lib libmzgcxxxxxxx.lib --dllname libmzgcxxxxxxx.dll
-	cd ../..; if [ ! -d $(ILIBDIR) ] ; then mkdir $(ILIBDIR) ; fi
-	cd ../..; if [ ! -d $(ILIBDIR)/gcc ] ; then mkdir $(ILIBDIR)/gcc ; fi
+	cd ../..; mkdir -p $(ILIBDIR)/gcc
 	cd ../..; cp mzscheme/dynsrc/mzdynx.def $(ILIBDIR)/gcc/mzdyn.def
 	cd ../..; cp mzscheme/dynsrc/mzdyn.exp $(ILIBDIR)/gcc
 	cd ../..; cp mzscheme/dynsrc/mzdyn.o $(ILIBDIR)/gcc
diff --git a/src/mzscheme/gc2/Makefile.in b/src/mzscheme/gc2/Makefile.in
index 64865827ba..acbad6447e 100644
--- a/src/mzscheme/gc2/Makefile.in
+++ b/src/mzscheme/gc2/Makefile.in
@@ -308,18 +308,16 @@ EXTRA_OBJS_L = ../src/gmp.@LTO@ @FOREIGN_OBJSLIB_IF_USED@
 MZFWMMM = PLT_MzScheme.framework/Versions/$(FWVERSION)_3m/PLT_MzScheme
 
 $(MZFWMMM): ../libmzscheme3m.@LIBSFX@
-	if [ ! -d PLT_MzScheme.framework ] ; then mkdir PLT_MzScheme.framework ; fi
-	if [ ! -d PLT_MzScheme.framework/Versions ] ; then mkdir PLT_MzScheme.framework/Versions ; fi
-	if [ ! -d PLT_MzScheme.framework/Versions/$(FWVERSION)_3m ] ; then mkdir PLT_MzScheme.framework/Versions/$(FWVERSION)_3m ; fi
+	mkdir -p "PLT_MzScheme.framework/Versions/$(FWVERSION)_3m"
 	$(CC) -o $(MZFWMMM) -framework CoreFoundation -dynamiclib -all_load ../libmzscheme3m.@LIBSFX@ @LDFLAGS@ $(LIBS)
 	rm -f PLT_MzScheme.framework/PLT_MzScheme
 	ln -s Versions/$(FWVERSION)_3m/PLT_MzScheme PLT_MzScheme.framework/PLT_MzScheme	
 
 ../mzscheme3m@OSX@: $(MZFWMMM) main.@LTO@
 	$(CC) -o ../mzscheme3m @PROFFLAGS@ main.@LTO@ -Wl,-headerpad_max_install_names -F. -framework PLT_MzScheme
-	if [ ! -d ../PLT_MzScheme.framework/Versions/$(FWVERSION)_3m ] ; then mkdir ../PLT_MzScheme.framework/Versions/$(FWVERSION)_3m ; fi
-	cp PLT_MzScheme.framework/Versions/$(FWVERSION)_3m/PLT_MzScheme ../PLT_MzScheme.framework/Versions/$(FWVERSION)_3m/PLT_MzScheme
-	/usr/bin/install_name_tool -change "PLT_MzScheme.framework/Versions/$(FWVERSION)_3m/PLT_MzScheme" "@executable_path/PLT_MzScheme.framework/Versions/$(FWVERSION)_3m/PLT_MzScheme" ../mzscheme3m
+	mkdir -p "../PLT_MzScheme.framework/Versions/$(FWVERSION)_3m"
+	cp "PLT_MzScheme.framework/Versions/$(FWVERSION)_3m/PLT_MzScheme" "../PLT_MzScheme.framework/Versions/$(FWVERSION)_3m/PLT_MzScheme"
+	/usr/bin/install_name_tool -change "PLT_MzScheme.framework/Versions/$(FWVERSION)_3m/PLT_MzScheme" "@executable_path/PLT_MzScheme.framework/Versions/$(FWVERSION)_3m/PLT_MzScheme" "../mzscheme3m"
 
 
 clean: