diff -r f5bdca63bbe7 -r 27f8a41882a7 configure
--- a/configure	Tue Aug 13 21:13:43 2019 +0200
+++ b/configure	Tue Aug 13 21:50:16 2019 +0200
@@ -186,6 +186,16 @@
     done
     return 1
 }
+isnotplatform()
+{
+    for p in $PLATFORM
+    do
+        if [ $p = $1 ]; then
+            return 1
+        fi
+    done
+    return 0
+}
 
 # generate config.mk and config.h
 cat > $TEMP_DIR/config.mk << __EOF__
@@ -252,8 +262,8 @@
         if ! $PKG_CONFIG libpq ; then
             break
         fi
-        CFLAGS+=" `$PKG_CONFIG --cflags libpq`"
-        LDFLAGS+=" `$PKG_CONFIG --libs libpq`"
+        CFLAGS="$CFLAGS `$PKG_CONFIG --cflags libpq`"
+        LDFLAGS="$LDFLAGS `$PKG_CONFIG --libs libpq`"
 		echo yes
         return 0
     done
@@ -273,8 +283,8 @@
         if ! $PKG_CONFIG openssl ; then
             break
         fi
-        CFLAGS+=" `$PKG_CONFIG --cflags openssl`"
-        LDFLAGS+=" `$PKG_CONFIG --libs openssl`"
+        CFLAGS="$CFLAGS `$PKG_CONFIG --cflags openssl`"
+        LDFLAGS="$LDFLAGS `$PKG_CONFIG --libs openssl`"
 		echo yes
         return 0
     done
@@ -294,8 +304,8 @@
         if ! $PKG_CONFIG libxml-2.0 ; then
             break
         fi
-        CFLAGS+=" `$PKG_CONFIG --cflags libxml-2.0`"
-        LDFLAGS+=" `$PKG_CONFIG --libs libxml-2.0`"
+        CFLAGS="$CFLAGS `$PKG_CONFIG --cflags libxml-2.0`"
+        LDFLAGS="$LDFLAGS `$PKG_CONFIG --libs libxml-2.0`"
 		echo yes
         return 0
     done
@@ -311,14 +321,14 @@
 LDFLAGS=
 while true
 do
-    if ! isplatform "linux"; then
+    if isnotplatform "linux"; then
         break
     fi
     while true
     do
         
-        CFLAGS+="-DLINUX"    
-        LDFLAGS+="-lpthread -ldl -lm -lldap"    
+        CFLAGS="CFLAGS -DLINUX"    
+        LDFLAGS="LDFLAGS -lpthread -ldl -lm -lldap"    
 		cat >> $TEMP_DIR/make.mk << __EOF__
 # platform dependend source files
 PLATFORM_DAEMONOBJ = event_linux.o
@@ -337,7 +347,7 @@
 done
 while true
 do
-    if ! isplatform "bsd"; then
+    if isnotplatform "bsd"; then
         break
     fi
     if isplatform "macos"; then
@@ -346,8 +356,8 @@
     while true
     do
         
-        CFLAGS+="-DBSD"    
-        LDFLAGS+="-lpthread -lm -lldap"    
+        CFLAGS="CFLAGS -DBSD"    
+        LDFLAGS="LDFLAGS -lpthread -lm -lldap"    
 		cat >> $TEMP_DIR/make.mk << __EOF__
 # platform dependend source files
 PLATFORM_DAEMONOBJ = event_bsd.o
@@ -366,14 +376,14 @@
 done
 while true
 do
-    if ! isplatform "macos"; then
+    if isnotplatform "macos"; then
         break
     fi
     while true
     do
         
-        CFLAGS+="-DBSD -DOSX"    
-        LDFLAGS+="-lpthread -ldl -lm -lldap"    
+        CFLAGS="CFLAGS -DBSD -DOSX"    
+        LDFLAGS="LDFLAGS -lpthread -ldl -lm -lldap"    
 		cat >> $TEMP_DIR/make.mk << __EOF__
 # platform dependend source files
 PLATFORM_DAEMONOBJ = event_bsd.o
@@ -392,14 +402,14 @@
 done
 while true
 do
-    if ! isplatform "solaris"; then
+    if isnotplatform "solaris"; then
         break
     fi
     while true
     do
         
-        CFLAGS+="-DSOLARIS -D_REENTRANT -D_POSIX_PTHREAD_SEMANTICS"    
-        LDFLAGS+="-lsocket -lnsl -lsendfile -lposix4 -lpthread -ldl -lm -lmd -lldap"    
+        CFLAGS="CFLAGS -DSOLARIS -D_REENTRANT -D_POSIX_PTHREAD_SEMANTICS"    
+        LDFLAGS="LDFLAGS -lsocket -lnsl -lsendfile -lposix4 -lpthread -ldl -lm -lmd -lldap"    
 		cat >> $TEMP_DIR/make.mk << __EOF__
 # platform dependend source files
 PLATFORM_DAEMONOBJ = event_solaris.o
@@ -447,12 +457,12 @@
 
 dependency_libxml2
 if [ $? -ne 0 ]; then
-	DEPENDENCIES_FAILED+="libxml2 "
+	DEPENDENCIES_FAILED="$DEPENDENCIES_FAILED libxml2 "
 	ERROR=1
 fi
 dependency_openssl
 if [ $? -ne 0 ]; then
-	DEPENDENCIES_FAILED+="openssl "
+	DEPENDENCIES_FAILED="$DEPENDENCIES_FAILED openssl "
 	ERROR=1
 fi