diff --git a/.bintray_descriptor.json b/.bintray_descriptor.json
index 5d244a4f7..ff3e91669 100644
--- a/.bintray_descriptor.json
+++ b/.bintray_descriptor.json
@@ -13,7 +13,7 @@
     },
 
     "version": {
-        "name": "0.2.1",
+        "name": "0.2.2",
         "desc": "HermitCore's kernel as libOS",
         "gpgSign": false
     },
diff --git a/.travis.yml b/.travis.yml
index d9c3418c7..29be05dd3 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,7 +3,9 @@ dist: trusty
 git:
   submodules: true
 language: c
-compiler: gcc
+compiler:
+  - clang
+  - gcc
 before_install:
   - echo "deb https://dl.bintray.com/rwth-os/hermitcore vivid main" | sudo tee -a /etc/apt/sources.list
   - travis_retry sudo apt-get -qq update
@@ -24,7 +26,9 @@ notifications:
   slack: hermitcore:UtcfeEXkbpx3WyIDK2Wm2beS
 
 deploy:
-  on: master
+  on: 
+    branch: master
+    condition: "$CC = gcc"
   provider: bintray
   file: .bintray_descriptor.json
   user:
diff --git a/CMakeLists.txt b/CMakeLists.txt
index bea2e2ab7..ef41c0992 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -199,7 +199,7 @@ set(CPACK_SYSTEM_NAME all)
 
 set(CPACK_PACKAGE_VERSION_MAJOR 0)
 set(CPACK_PACKAGE_VERSION_MINOR 2)
-set(CPACK_PACKAGE_VERSION_PATCH 1)
+set(CPACK_PACKAGE_VERSION_PATCH 2)
 
 set(CPACK_PACKAGE_CONTACT "Stefan Lankes <slankes@eonerc.rwth-aachen.de>")
 
diff --git a/arch/x86/kernel/apic.c b/arch/x86/kernel/apic.c
index 1192490b8..f75d7fff7 100644
--- a/arch/x86/kernel/apic.c
+++ b/arch/x86/kernel/apic.c
@@ -905,12 +905,7 @@ extern int set_idle_task(void);
 #if MAX_CORES > 1
 int smp_start(void)
 {
-	x2apic_enable();
-
-	// reset APIC and set id
-	lapic_reset();
-
-	LOG_DEBUG("Processor %d (local id %d) is entering its idle task\n", apic_cpu_id(), atomic_int32_read(&current_boot_id));
+	LOG_DEBUG("Try to initialize processor (local id %d)\n", atomic_int32_read(&current_boot_id));
 
 	// use the same gdt like the boot processors
 	gdt_flush();
@@ -921,6 +916,12 @@ int smp_start(void)
 	// enable additional cpu features
 	cpu_detection();
 
+	x2apic_enable();
+
+	// reset APIC
+	lapic_reset();
+
+	LOG_DEBUG("Processor %d (local id %d) is entering its idle task\n", apic_cpu_id(), atomic_int32_read(&current_boot_id));
 	LOG_DEBUG("CR0 of core %u: 0x%x\n", atomic_int32_read(&current_boot_id), read_cr0());
 	online[atomic_int32_read(&current_boot_id)] = 1;
 
diff --git a/arch/x86/kernel/entry.asm b/arch/x86/kernel/entry.asm
index 6375533da..5775dfbcc 100644
--- a/arch/x86/kernel/entry.asm
+++ b/arch/x86/kernel/entry.asm
@@ -121,10 +121,11 @@ SECTION .ktext
 align 4
 start64:
     ; reset registers to kill any stale realmode selectors
-    xor eax, eax
+    mov eax, 0x10
     mov ds, eax
     mov ss, eax
     mov es, eax
+    xor eax, eax
     mov fs, eax
     mov gs, eax
 
@@ -263,7 +264,22 @@ extern gp
 ; C as 'extern void gdt_flush();'
 gdt_flush:
     lgdt [gp]
-    ret
+    ; reload the segment descriptors
+    mov eax, 0x10
+    mov ds, eax
+    mov es, eax
+    mov ss, eax
+    xor eax, eax
+    mov fs, eax
+    mov gs, eax
+    ; create pseudo interrupt to set cs
+    push QWORD 0x10             ; SS
+    push rsp                    ; RSP
+    add QWORD [rsp], 0x08       ; => value of rsp before the creation of a pseudo interrupt
+    pushfq                      ; RFLAGS
+    push QWORD 0x08             ; CS
+    push QWORD rollback         ; RIP
+    iretq
 
 ; The first 32 interrupt service routines (ISR) entries correspond to exceptions.
 ; Some exceptions will push an error code onto the stack which is specific to
diff --git a/arch/x86/kernel/gdt.c b/arch/x86/kernel/gdt.c
index 2eca34564..8c1149c9f 100644
--- a/arch/x86/kernel/gdt.c
+++ b/arch/x86/kernel/gdt.c
@@ -153,7 +153,7 @@ void gdt_install(void)
 		task_state_segments[i].ist3 = (size_t) stack_table[i] + (3 /*IST number */ - 1) * KERNEL_STACK_SIZE - 0x10;
 		task_state_segments[i].ist4 = (size_t) stack_table[i] + (4 /*IST number */ - 1) * KERNEL_STACK_SIZE - 0x10;
 
-		gdt_set_gate(num+i*2, (unsigned long) (task_state_segments+i), sizeof(tss_t)-1,
+		gdt_set_gate(num+i*2, (unsigned long) (task_state_segments+i), sizeof(tss_t),
 			GDT_FLAG_PRESENT | GDT_FLAG_TSS | GDT_FLAG_RING0, 0);
 	}
 
diff --git a/arch/x86/loader/CMakeLists.txt b/arch/x86/loader/CMakeLists.txt
index b9ea11d7e..99bc4081a 100644
--- a/arch/x86/loader/CMakeLists.txt
+++ b/arch/x86/loader/CMakeLists.txt
@@ -17,14 +17,33 @@ target_include_directories(arch_x86_loader
 
 target_compile_options(arch_x86_loader
 	PRIVATE -O2 -Wall -m64 -std=gnu99 -ffreestanding -mno-red-zone
-			-fstrength-reduce -fomit-frame-pointer -finline-functions)
+			-fomit-frame-pointer -fno-builtin -nostdlib -nostdinc -mno-sse -mno-avx -mno-mmx -mno-3dnow)
 
-target_link_libraries(arch_x86_loader
-	arch_x86_loader_asm
-	"-T ${CMAKE_CURRENT_LIST_DIR}/link.ld"
-	"-z max-page-size=4096"
-	-Wl,--build-id=none		# required because CMake links with gcc, not ld
-	-nostdlib -static)
+include(CheckCCompilerFlag)
+check_c_compiler_flag(-fstrength-reduce HAS_STRENGTH_REDUCE)
+if (HAS_STRENGTH_REDUCE)
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -fstrength-reduce")
+endif()
+
+check_c_compiler_flag(-finline-functions HAS_INLINE_FUNCTIONS)
+if (HAS_INLINE_FUNCTIONS)
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -finline-functions")
+endif()
+
+set(CMAKE_LINKER_NAME ld CACHE STRING "Name of the binutils linker")
+mark_as_advanced(CMAKE_LINKER_NAME)
+
+find_program(CMAKE_LINKER ${CMAKE_LINKER_NAME})
+mark_as_advanced(CMAKE_LINKER)
+
+if(NOT CMAKE_LINKER)
+	message(FATAL_ERROR "Could not find the GNU LD linker: ${CMAKE_LINKER_NAME}")
+endif()
+
+set(CMAKE_C_LINK_EXECUTABLE "${CMAKE_LINKER} <CMAKE_C_LINK_FLAGS> <LINK_FLAGS> <OBJECTS> -o <TARGET> <LINK_LIBRARIES>")
+set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -T ${CMAKE_CURRENT_LIST_DIR}/link.ld -z max-page-size=4096 --build-id=none -nostdlib -static")
+
+target_link_libraries(arch_x86_loader arch_x86_loader_asm)
 
 # tools/proxy looks for `ldhermit.elf`
 set_target_properties(arch_x86_loader PROPERTIES
diff --git a/arch/x86/loader/include/ctype.h b/arch/x86/loader/include/ctype.h
index c5aa3915b..597c6d286 100644
--- a/arch/x86/loader/include/ctype.h
+++ b/arch/x86/loader/include/ctype.h
@@ -25,7 +25,7 @@
  */
 
 #ifndef __CTYPE_H_
-#define __CYTPE_H_
+#define __CTYPE_H_
 
 /** Returns true if the value of 'c' is an ASCII-charater */
 static inline int isascii(int c) 
diff --git a/arch/x86/loader/page.c b/arch/x86/loader/page.c
index 0cab29437..80c4cdedd 100644
--- a/arch/x86/loader/page.c
+++ b/arch/x86/loader/page.c
@@ -56,12 +56,6 @@ static size_t * const self[PAGE_LEVELS] = {
 	(size_t *) 0xFFC00000,
 	(size_t *) 0xFFFFF000
 };
-
-/** An other self-reference for page_map_copy() */
-static size_t * const other[PAGE_LEVELS] = {
-	(size_t *) 0xFF800000,
-	(size_t *) 0xFFFFE000
-};
 #elif defined(CONFIG_X86_64)
 /** A self-reference enables direct access to all page tables */
 static size_t* const self[PAGE_LEVELS] = {
@@ -70,14 +64,6 @@ static size_t* const self[PAGE_LEVELS] = {
 	(size_t *) 0xFFFFFFFFFFE00000,
 	(size_t *) 0xFFFFFFFFFFFFF000
 };
-
-/** An other self-reference for page_map_copy() */
-static size_t * const other[PAGE_LEVELS] = {
-	(size_t *) 0xFFFFFF0000000000,
-	(size_t *) 0xFFFFFFFF80000000,
-	(size_t *) 0xFFFFFFFFFFC00000,
-	(size_t *) 0xFFFFFFFFFFFFE000
-};
 #endif
 
 /** @brief Flush a specific page entry in TLB
diff --git a/arch/x86/loader/uart.c b/arch/x86/loader/uart.c
index 5d0599843..2437fd2ff 100644
--- a/arch/x86/loader/uart.c
+++ b/arch/x86/loader/uart.c
@@ -96,7 +96,7 @@ size_t	uartport = 0;
 
 static inline unsigned char read_from_uart(uint32_t off)
 {
-	uint8_t c;
+	uint8_t c = 0;
 
 	if (uartport)
 		c = inportb(uartport + off);
diff --git a/cmake/HermitCore-Configuration.cmake b/cmake/HermitCore-Configuration.cmake
index bd5753eef..c38566f8c 100644
--- a/cmake/HermitCore-Configuration.cmake
+++ b/cmake/HermitCore-Configuration.cmake
@@ -1,4 +1,4 @@
-set(PACKAGE_VERSION "0.2.1" CACHE STRING
+set(PACKAGE_VERSION "0.2.2" CACHE STRING
 	"HermitCore current version")
 
 set(MAX_CORES "512" CACHE STRING
diff --git a/drivers/net/e1000.c b/drivers/net/e1000.c
index c460f96f6..330c16f5c 100644
--- a/drivers/net/e1000.c
+++ b/drivers/net/e1000.c
@@ -45,6 +45,8 @@
 #include <netif/etharp.h>
 #include <net/e1000.h>
 
+#if USE_E1000
+
 #define RX_BUF_LEN      (2048)
 #define TX_BUF_LEN      (1792)
 
@@ -603,3 +605,5 @@ oom:
 
 	return ERR_MEM;
 }
+
+#endif
diff --git a/drivers/net/e1000.h b/drivers/net/e1000.h
index 08f0d886f..49ade1225 100644
--- a/drivers/net/e1000.h
+++ b/drivers/net/e1000.h
@@ -32,6 +32,8 @@
 #include <hermit/stddef.h>
 #include <hermit/spinlock.h>
 
+#ifdef USE_E1000
+
 #define NUM_RX_DESCRIPTORS	64
 #define NUM_TX_DESCRIPTORS	64
 
@@ -324,3 +326,5 @@ typedef struct e1000if {
 err_t e1000if_init(struct netif* netif);
 
 #endif
+
+#endif
diff --git a/kernel/main.c b/kernel/main.c
index d2fe61327..b5c0bf214 100644
--- a/kernel/main.c
+++ b/kernel/main.c
@@ -206,8 +206,10 @@ static int init_netifs(void)
 			goto success;
 		if ((err = netifapi_netif_add(&default_netif, ip_2_ip4(&ipaddr), ip_2_ip4(&netmask), ip_2_ip4(&gw), NULL, rtl8139if_init, ethernet_input)) == ERR_OK)
 			goto success;
+#ifdef USE_E1000
 		if ((err = netifapi_netif_add(&default_netif, ip_2_ip4(&ipaddr), ip_2_ip4(&netmask), ip_2_ip4(&gw), NULL, e1000if_init, ethernet_input)) == ERR_OK)
 			goto success;
+#endif
 
 		LOG_ERROR("Unable to add the network interface: err = %d\n", err);
 
diff --git a/lwip b/lwip
index 51d48fe0c..c21d911aa 160000
--- a/lwip
+++ b/lwip
@@ -1 +1 @@
-Subproject commit 51d48fe0c67131da346c9ef280b2019c77f6e607
+Subproject commit c21d911aa4f178563dc102f595d1d97dd8471458
diff --git a/tests.sh b/tests.sh
index 3cabbadbe..a4e8f0639 100755
--- a/tests.sh
+++ b/tests.sh
@@ -9,6 +9,8 @@ PROXY=build/local_prefix/opt/hermit/bin/proxy
 
 for f in $FILES; do echo "check $f..."; HERMIT_ISLE=qemu HERMIT_CPUS=1 HERMIT_KVM=0 HERMIT_VERBOSE=1 timeout --kill-after=5m 5m $PROXY $f || exit 1; done
 
+for f in $FILES; do echo "check $f..."; HERMIT_ISLE=qemu HERMIT_CPUS=2 HERMIT_KVM=0 HERMIT_VERBOSE=1 timeout --kill-after=5m 5m $PROXY $f || exit 1; done
+
 # test echo server at port 8000
 HERMIT_ISLE=qemu HERMIT_CPUS=1 HERMIT_KVM=0 HERMIT_VERBOSE=1 HERMIT_APP_PORT=8000 $PROXY $TDIR/tests/server &
 sleep 10
diff --git a/tools/uhyve.c b/tools/uhyve.c
index da84a3276..64298e1bf 100644
--- a/tools/uhyve.c
+++ b/tools/uhyve.c
@@ -591,7 +591,7 @@ static void show_registers(int id, struct kvm_regs* regs, struct kvm_sregs* sreg
 	fprintf(stderr, "\n");
 }
 
-static int print_registers(void)
+static void print_registers(void)
 {
 	struct kvm_regs regs;
 	struct kvm_sregs sregs;