diff --git a/Makefile b/Makefile
index 71e74a6..a9242fb 100644
--- a/Makefile
+++ b/Makefile
@@ -25,3 +25,23 @@ tests:
 	make tests -f Makefile.out.2
 	rm Makefile.out Makefile.out.2
 
+ASM=nasm
+ASMFLAGS=
+BOOTFLAGS=-f bin
+
+BOOTDIR=boot
+OBJDIR=build/obj
+BINDIR=build/bin
+
+boot.mbr.asm: $(BOOTDIR)/mbr.asm $(BOOTDIR)/mbr.inc
+	$(ASM) $(BOOTFLAGS) $(BOOTDIR)/mbr.asm -o $(OBJDIR)/boot/mbr.bin
+
+boot.loader.asm: $(BOOTDIR)/loader.asm
+	$(ASM) $(BOOTFLAGS) $(BOOTDIR)/loader.asm -o $(OBJDIR)/boot/loader.bin
+
+bootloader: boot.mbr.asm boot.loader.asm
+	cp $(OBJDIR)/boot/mbr.bin $(BINDIR)/mbr.bin
+	cp $(OBJDIR)/boot/loader.bin $(BINDIR)/loader.bin
+
+all: bootloader kernel
+
diff --git a/Makefile.in b/Makefile.in
index 5c26235..3b7a9c6 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -22,10 +22,6 @@ CFLAGS=$(CFLAGS1) $(CFLAGS2) $(SFLAG)
 
 CC=$(CCNAME) $(COPTIM) $(CWARNS) $(CFLAGS) $(CINCLUDES)
 
-ASM=nasm
-ASMFLAGS=
-BOOTFLAGS=-f bin
-
 BINDIR=./build/bin
 OBJDIR=./build/obj
 
@@ -35,18 +31,6 @@ KERNDIR=kaleid/kernel
 SYSTDIR=kaleid/system
 LINXDIR=kaleid/common/test
 
-all: bootloader kernel
-
-boot.mbr.s: $(BOOTDIR)/mbr.s $(BOOTDIR)/mbr.inc
-	$(ASM) $(BOOTFLAGS) $(BOOTDIR)/mbr.asm -o $(OBJDIR)/boot/mbr.bin
-
-boot.loader.s: $(BOOTDIR)/loader.s
-	$(ASM) $(BOOTFLAGS) $(BOOTDIR)/loader.asm -o $(OBJDIR)/boot/loader.bin
-
-bootloader: boot.mbr.s boot.loader.s
-	cp $(OBJDIR)/boot/mbr.bin $(BINDIR)/mbr.bin
-	cp $(OBJDIR)/boot/loader.bin $(BINDIR)/loader.bin
-
 //----------------------------------------------------------------------------#
 // TESTING MAKEFILE
 
diff --git a/ProjectTree b/ProjectTree
index 90c5627..965face 100644
--- a/ProjectTree
+++ b/ProjectTree
@@ -60,8 +60,6 @@ src/
     |   |
     |   + kernel/
     |   |   |
-    |   |   - kernel.ld
-    |   |   |
     |   |   + init/
     |   |   |   |
     |   |   |   - init.c
@@ -99,6 +97,8 @@ src/
     |   |
     |   - preproc.h
     |   - iddtool.h
+    |	|
+    |	- kernel.ld
     |   |
     |   + bin/
     |   + obj/
diff --git a/kaleid/common/atoi.c b/kaleid/common/atoi.c
index f5a22a6..0ea016c 100644
--- a/kaleid/common/atoi.c
+++ b/kaleid/common/atoi.c
@@ -15,9 +15,9 @@
 //
 #define _ATOI_IMPL(_Name, _Type, _Func)             \
     _Type _Name(const char *str) {                  \
-        error_t old = errno;                        \
+        __get_errno(old);                           \
         _Type ret = (_Type)_Func(str, NULL, 0);     \
-        errno = old;                                \
+        __set_errno(old);                           \
         return ret;                                 \
     }
 
diff --git a/kaleid/common/status.c b/kaleid/common/status.c
index 457e741..2866833 100644
--- a/kaleid/common/status.c
+++ b/kaleid/common/status.c
@@ -9,7 +9,7 @@
 
 #include <kaleid.h>
 
-error_t errno = 0;
+error_t __errno = 0;
 
 /*
 static const char *descriptions[] = {
@@ -17,7 +17,7 @@ static const char *descriptions[] = {
     [-FAILED]               = "Failed (no precision)",
     [-NOT_PERMITTED]        = "Operation not permitted",
     [-ACCESS_DENIED]        = "Access denied",
-    
+
     [-BAD_ARGUMENT]         = "Bad argument",
     [-BAD_ARG_RANGE]        = "Bad argument (not in range)",
     [-BAD_ARG_NULL]         = "Bad argument (null pointer)",
diff --git a/kaleid/common/strtol.c b/kaleid/common/strtol.c
index 2e1aad6..7636822 100644
--- a/kaleid/common/strtol.c
+++ b/kaleid/common/strtol.c
@@ -13,7 +13,7 @@ long strtol(const char *str, char **endp, int base) {
     (void)str;
     (void)endp;
     (void)base;
-    errno = ENOSYS;
+    __set_errno(ENOSYS);
     return 0;
 }
 
@@ -21,7 +21,7 @@ ulong strtoul(const char *str, char **endp, int base) {
     (void)str;
     (void)endp;
     (void)base;
-    errno = ENOSYS;
+    __set_errno(ENOSYS);
     return 0;
 }
 
diff --git a/kaleid/include/common/kalcrt.h b/kaleid/include/common/kalcrt.h
index 75e34e1..167ab52 100644
--- a/kaleid/include/common/kalcrt.h
+++ b/kaleid/include/common/kalcrt.h
@@ -43,7 +43,24 @@ typedef struct { long quot, rem; }  ldiv_t;
 //              Global variables            //
 //------------------------------------------//
 
-extern error_t errno;
+#ifndef _KALEID_KERNEL
+
+extern error_t __errno;
+
+#ifndef errno
+#define errno __errno
+#endif
+
+#define __get_errno(x) error_t x = errno;
+#define __set_errno(x) (errno = (x))
+
+#else
+
+#define errno
+#define __get_errno(x)
+#define __set_errno(x)
+
+#endif
 
 //------------------------------------------//
 //                 Macros                   //
diff --git a/kaleid/include/kernel/kernbase.h b/kaleid/include/kernel/kernbase.h
index 171c048..baf8e95 100644
--- a/kaleid/include/kernel/kernbase.h
+++ b/kaleid/include/kernel/kernbase.h
@@ -184,7 +184,8 @@ void WriteByteOnPort(port_t port, port_t val)
 static inline
 uchar ReadByteFromPort(port_t port)
 {
-    errno = ENOSYS;
+
+    KalAssert(FALSE && ENOSYS);
     (void)port;
     return 0;
 }
@@ -192,7 +193,7 @@ uchar ReadByteFromPort(port_t port)
 static inline
 ushort ReadWordFromPort(port_t port)
 {
-    errno = ENOSYS;
+    KalAssert(FALSE && ENOSYS);
     (void)port;
     return 0;
 }