improved coding style

Makefile

@@ -21,27 +21,9 @@ LIBTOOLIZE := $(shell glibtoolize --help >/dev/null 2>&1 && echo g)libtoolize
 VERSION    := $(shell $(SED) -n 's,^.*<span id="latest-version">\([^<]*\)</span>.*$$,\1,p' '$(TOP_DIR)/doc/index.html')
 
 # unexport any environment variables that might cause trouble
-unexport AR
-unexport CC
-unexport CFLAGS
-unexport CPP
-unexport CPPFLAGS
-unexport CROSS
-unexport CXX
-unexport CXXCPP
-unexport CXXFLAGS
-unexport EXEEXT
-unexport EXTRA_CFLAGS
-unexport EXTRA_LDFLAGS
-unexport LD
-unexport LDFLAGS
-unexport LIBS
-unexport NM
-unexport PKG_CONFIG
-unexport PKG_CONFIG_PATH
-unexport QMAKESPEC
-unexport RANLIB
-unexport STRIP
+unexport AR CC CFLAGS CPP CPPFLAGS CROSS CXX CXXCPP CXXFLAGS EXEEXT
+unexport EXTRA_CFLAGS EXTRA_LDFLAGS LD LDFLAGS LIBS NM PKG_CONFIG
+unexport PKG_CONFIG_PATH QMAKESPEC RANLIB STRIP
 
 SHORT_PKG_VERSION = \
     $(word 1,$(subst ., ,$($(1)_VERSION))).$(word 2,$(subst ., ,$($(1)_VERSION)))