Use -n "$()" instead of "$()" != ""

build-libssp.sh

@@ -22,7 +22,7 @@ if [ $# -lt 1 ]; then
 fi
 
 MAKE=make
-if [ "$(which gmake)" != "" ]; then
+if [ -n "$(which gmake)" ]; then
     MAKE=gmake
 fi
 

build-mingw-w64-tools.sh

@@ -49,7 +49,7 @@ fi
 cd mingw-w64
 
 MAKE=make
-if [ "$(which gmake)" != "" ]; then
+if [ -n "$(which gmake)" ]; then
     MAKE=gmake
 fi
 

build-mingw-w64.sh

@@ -62,7 +62,7 @@ fi
 [ -z "$CHECKOUT_ONLY" ] || exit 0
 
 MAKE=make
-if [ "$(which gmake)" != "" ]; then
+if [ -n "$(which gmake)" ]; then
     MAKE=gmake
 fi