diff --git a/src/acc/acc.h b/src/acc/acc.h
index 9a52d709..f21190b9 100644
--- a/src/acc/acc.h
+++ b/src/acc/acc.h
@@ -27,7 +27,7 @@
 #ifndef __ACC_H_INCLUDED
 #define __ACC_H_INCLUDED 1
 
-#define ACC_VERSION     20040202L
+#define ACC_VERSION     20040511L
 
 #if !defined(ACC_CONFIG_INCLUDE)
 #  define ACC_CONFIG_INCLUDE(file)     file
@@ -45,18 +45,23 @@
 #endif
 
 
-/* disable pedantic warnings */
+/* disable pedantic warnings for undefined preprocessing symbols */
 #if defined(__INTEL_COMPILER) && defined(__linux__)
-#  pragma warning(disable: 193)     /* #193: zero used for undefined preprocessing identifier */
+#  pragma warning(disable: 193)
+#endif
+#if defined(__KEIL__) && defined(__C166__)
+#  pragma warning disable = 322
+#elif 0 && defined(__C251__)
+#  pragma warning disable = 322
 #endif
 #if defined(_MSC_VER) && !defined(__INTEL_COMPILER)
 #  if (_MSC_VER >= 1300)
-#    pragma warning(disable: 4668)  /* -Wall: 4668: 'symbol' is not defined as a preprocessor macro, replacing with '0' */
+#    pragma warning(disable: 4668)
 #  endif
 #endif
 #if 0 && defined(__WATCOMC__)
 #  if (__WATCOMC__ < 1060)
-#    pragma warning 203 9           /* W203: Preprocessing symbol '%s' has not been declared */
+#    pragma warning 203 9
 #  endif
 #endif
 
@@ -65,8 +70,8 @@
 #include ACC_CONFIG_INCLUDE("acc_init.h")
 #include ACC_CONFIG_INCLUDE("acc_os.h")
 #include ACC_CONFIG_INCLUDE("acc_cc.h")
-#include ACC_CONFIG_INCLUDE("acc_mm.h")
 #include ACC_CONFIG_INCLUDE("acc_arch.h")
+#include ACC_CONFIG_INCLUDE("acc_mm.h")
 #include ACC_CONFIG_INCLUDE("acc_defs.h")
 
 #if defined(ACC_CONFIG_NO_HEADER)
diff --git a/src/acc/acc_arch.h b/src/acc/acc_arch.h
index b720beee..8f83583f 100644
--- a/src/acc/acc_arch.h
+++ b/src/acc/acc_arch.h
@@ -18,11 +18,14 @@
  *
  *   ACC_ARCH_UNKNOWN       [default]
  *   ACC_ARCH_ALPHA
- *   ACC_ARCH_AMD64
+ *   ACC_ARCH_AMD64         aka x86-64 or ia32e
+ *   ACC_ARCH_C166
  *   ACC_ARCH_IA16          Intel Architecture (8088, 8086, 80186, 80286)
  *   ACC_ARCH_IA32          Intel Architecture (80386+)
  *   ACC_ARCH_IA64          Intel Architecture (Itanium)
  *   ACC_ARCH_M68K          Motorola 680x0
+ *   ACC_ARCH_MCS251
+ *   ACC_ARCH_MCS51
  *   ACC_ARCH_PPC64         Power PC
  *   ACC_ARCH_SPARC64
  *
@@ -41,6 +44,18 @@
 #elif defined(__amd64__) || defined(__x86_64__) || defined(_M_AMD64)
 #  define ACC_ARCH_AMD64            1
 #  define ACC_INFO_ARCH             "amd64"
+#elif (UINT_MAX <= ACC_0xffffL) && defined(__AVR__)
+#  define ACC_ARCH_AVR              1
+#  define ACC_INFO_ARCH             "avr"
+#elif (UINT_MAX == ACC_0xffffL) && defined(__C166__)
+#  define ACC_ARCH_C166             1
+#  define ACC_INFO_ARCH             "c166"
+#elif (UINT_MAX == ACC_0xffffL) && defined(__C251__)
+#  define ACC_ARCH_MCS251           1
+#  define ACC_INFO_ARCH             "mcs-251"
+#elif (UINT_MAX == ACC_0xffffL) && defined(__C51__)
+#  define ACC_ARCH_MCS51            1
+#  define ACC_INFO_ARCH             "mcs-51"
 #elif defined(__386__) || defined(__i386__) || defined(__i386) || defined(_M_IX86) || defined(_M_I386)
 #  define ACC_ARCH_IA32             1
 #  define ACC_INFO_ARCH             "ia32"
diff --git a/src/acc/acc_auto.h b/src/acc/acc_auto.h
index f7c9288d..f3f727d8 100644
--- a/src/acc/acc_auto.h
+++ b/src/acc/acc_auto.h
@@ -63,6 +63,7 @@
 #define HAVE_LIMITS_H 1
 #define HAVE_MALLOC_H 1
 #define HAVE_MEMORY_H 1
+#define HAVE_SETJMP_H 1
 #define HAVE_SIGNAL_H 1
 #define HAVE_STDARG_H 1
 #define HAVE_STDDEF_H 1
@@ -285,6 +286,7 @@
 #define HAVE_GETTIMEOFDAY 1
 #define HAVE_GMTIME 1
 #define HAVE_LOCALTIME 1
+#define HAVE_LONGJMP 1
 #define HAVE_LSTAT 1
 #define HAVE_MEMCMP 1
 #define HAVE_MEMCPY 1
@@ -293,6 +295,7 @@
 #define HAVE_MKTIME 1
 #define HAVE_QSORT 1
 #define HAVE_RAISE 1
+#define HAVE_SETJMP 1
 #define HAVE_SIGNAL 1
 #define HAVE_SNPRINTF 1
 #define HAVE_STAT 1
@@ -322,6 +325,7 @@
 #if (ACC_OS_POSIX)
 #  if (ACC_CC_TINYC)
 #    undef HAVE_ALLOCA
+#  elif defined(__dietlibc__)
 #  endif
 #  if (ACC_OS_POSIX_MACOSX && ACC_CC_MWERKS) && defined(__MSL__)
      /* FIXME ??? */
@@ -422,6 +426,9 @@
 #  if ((_MSC_VER < 800) && ACC_OS_WIN16)
 #    undef HAVE_ALLOCA
 #  endif
+#  if (_MSC_VER < 1000) && defined(__cplusplus)
+#    undef HAVE_SETJMP
+#  endif
 #elif (ACC_OS_WIN32 && ACC_CC_GNUC) && defined(__MINGW32__)
 #  if (ACC_CC_GNUC < 0x025f00ul)
 #    undef HAVE_SNPRINTF
@@ -554,6 +561,10 @@
 #  else
 #    error "ACC_MM"
 #  endif
+#elif (ACC_ARCH_AVR || ACC_ARCH_C166 || ACC_ARCH_MCS51 || ACC_ARCH_MCS251)
+#  define SIZEOF_PTRDIFF_T      2
+#  define SIZEOF_SIZE_T         2
+#  define SIZEOF_VOID_P         2
 #else
 #  define SIZEOF_PTRDIFF_T      SIZEOF_LONG
 #  define SIZEOF_SIZE_T         SIZEOF_LONG
diff --git a/src/acc/acc_cc.h b/src/acc/acc_cc.h
index 108818e5..557ea423 100644
--- a/src/acc/acc_cc.h
+++ b/src/acc/acc_cc.h
@@ -59,6 +59,10 @@
 #  define ACC_CC_IBMC           1
 #  define ACC_INFO_CC           "IBM C"
 #  define ACC_INFO_CCVER        ACC_CPP_MACRO_EXPAND(__IBMC__)
+#elif defined(__KEIL__) && defined(__C166__)
+#  define ACC_CC_KEILC          1
+#  define ACC_INFO_CC           "Keil C"
+#  define ACC_INFO_CCVER        ACC_CPP_MACRO_EXPAND(__C166__)
 #elif defined(__LCC__)
 #  define ACC_CC_LCC            1
 #  define ACC_INFO_CC           "lcc"
diff --git a/src/acc/acc_chk.ch b/src/acc/acc_chk.ch
index 97d3cb40..f9e77ea7 100644
--- a/src/acc/acc_chk.ch
+++ b/src/acc/acc_chk.ch
@@ -424,7 +424,9 @@
     ACCCHK_ASSERT( (int) ((unsigned char) ((signed char) -1)) == 255)
 #endif
 
-#if (ACC_CC_NDPC)
+#if (ACC_CC_KEILC)
+    /* Keil C is broken */
+#elif (ACC_CC_NDPC)
     /* NDP C is broken */
 #elif !defined(ACC_BROKEN_INTEGRAL_PROMOTION) && (SIZEOF_INT > 1)
     /* check that the compiler correctly promotes integrals */
diff --git a/src/acc/acc_defs.h b/src/acc/acc_defs.h
index bf80445b..6ffe3491 100644
--- a/src/acc/acc_defs.h
+++ b/src/acc/acc_defs.h
@@ -50,21 +50,29 @@
 ************************************************************************/
 
 #if !defined(ACC_UNUSED)
-#  if (ACC_CC_BORLANDC || ACC_CC_HIGHC || ACC_CC_NDPC || ACC_CC_TURBOC)
+#  if (ACC_CC_BORLANDC && (__BORLANDC__ >= 0x0600))
+#    define ACC_UNUSED(var)         ((void) &var)
+#  elif (ACC_CC_BORLANDC || ACC_CC_HIGHC || ACC_CC_NDPC || ACC_CC_TURBOC)
 #    define ACC_UNUSED(var)         if (&var) ; else
 #  elif (ACC_CC_MSC && (_MSC_VER < 900))
 #    define ACC_UNUSED(var)         if (&var) ; else
 #  elif (ACC_CC_GNUC)
 #    define ACC_UNUSED(var)         ((void) var)
+#  elif (ACC_CC_KEILC)
+#    define ACC_UNUSED(var)
 #  else
 #    define ACC_UNUSED(var)         ((void) &var)
 #  endif
 #endif
 #if !defined(ACC_UNUSED_FUNC)
-#  if (ACC_CC_BORLANDC || ACC_CC_NDPC || ACC_CC_TURBOC)
+#  if (ACC_CC_BORLANDC && (__BORLANDC__ >= 0x0600))
+#    define ACC_UNUSED_FUNC(func)   ((void) func)
+#  elif (ACC_CC_BORLANDC || ACC_CC_NDPC || ACC_CC_TURBOC)
 #    define ACC_UNUSED_FUNC(func)   if (func) ; else
 #  elif (ACC_CC_MSC && (_MSC_VER < 900))
 #    define ACC_UNUSED_FUNC(func)   if (func) ; else
+#  elif (ACC_CC_KEILC)
+#    define ACC_UNUSED_FUNC(func)
 #  else
 #    define ACC_UNUSED_FUNC(func)   ((void) func)
 #  endif
diff --git a/src/acc/acc_ince.h b/src/acc/acc_ince.h
index a0d2f5d6..9a0a081f 100644
--- a/src/acc/acc_ince.h
+++ b/src/acc/acc_ince.h
@@ -39,6 +39,9 @@
 #if defined(HAVE_DIRENT_H)
 #  include <dirent.h>
 #endif
+#if defined(HAVE_SETJMP_H)
+#  include <setjmp.h>
+#endif
 #if defined(HAVE_SIGNAL_H)
 #  include <signal.h>
 #endif
diff --git a/src/acc/acc_lib.h b/src/acc/acc_lib.h
index a16d6f3a..cd16fe8a 100644
--- a/src/acc/acc_lib.h
+++ b/src/acc/acc_lib.h
@@ -161,6 +161,8 @@ ACCLIB_EXTERN(acc_hsize_t, acc_hfwrite) (ACC_FILE_P, const acc_hvoid_p, acc_hsiz
 ACCLIB_EXTERN(long, acc_hread) (int, acc_hvoid_p, long);
 ACCLIB_EXTERN(long, acc_hwrite) (int, const acc_hvoid_p, long);
 #endif
+ACCLIB_EXTERN(long, acc_safe_hread) (int, acc_hvoid_p, long);
+ACCLIB_EXTERN(long, acc_safe_hwrite) (int, const acc_hvoid_p, long);
 
 
 /*************************************************************************
@@ -316,6 +318,13 @@ ACCLIB_EXTERN(acc_uint32l_t, acc_umuldiv32) (acc_uint32l_t, acc_uint32l_t, acc_u
 // uclock
 **************************************************************************/
 
+#if defined(acc_int32e_t)
+ACCLIB_EXTERN(int, acc_tsc_read) (acc_uint32e_t*);
+ACCLIB_EXTERN(int, acc_tsc_read_add) (acc_uint32e_t*);
+#define acc_rdtsc(x)    acc_tsc_read(x)
+#endif
+
+
 typedef struct { /* all private */
     acclib_handle_t h;
     int mode;
diff --git a/src/acc/acc_mm.h b/src/acc/acc_mm.h
index 4e82e7ad..4f1e3818 100644
--- a/src/acc/acc_mm.h
+++ b/src/acc/acc_mm.h
@@ -113,6 +113,61 @@ extern "C" {
 #endif
 
 
+#elif (ACC_ARCH_C166)
+#if !defined(__MODEL__)
+#  error "FIXME - C166 __MODEL__"
+#elif ((__MODEL__) == 0)
+#  define ACC_MM_SMALL          1
+#elif ((__MODEL__) == 1)
+#  define ACC_MM_SMALL          1
+#elif ((__MODEL__) == 2)
+#  define ACC_MM_LARGE          1
+#elif ((__MODEL__) == 3)
+#  define ACC_MM_TINY           1
+#elif ((__MODEL__) == 4)
+#  define ACC_MM_XTINY          1
+#elif ((__MODEL__) == 5)
+#  define ACC_MM_XSMALL         1
+#else
+#  error "FIXME - C166 __MODEL__"
+#endif
+
+
+#elif (ACC_ARCH_MCS251)
+#if !defined(__MODEL__)
+#  error "FIXME - MCS251 __MODEL__"
+#elif ((__MODEL__) == 0)
+#  define ACC_MM_SMALL          1
+#elif ((__MODEL__) == 2)
+#  define ACC_MM_LARGE          1
+#elif ((__MODEL__) == 3)
+#  define ACC_MM_TINY           1
+#elif ((__MODEL__) == 4)
+#  define ACC_MM_XTINY          1
+#elif ((__MODEL__) == 5)
+#  define ACC_MM_XSMALL         1
+#else
+#  error "FIXME - MCS251 __MODEL__"
+#endif
+
+
+#elif (ACC_ARCH_MCS51)
+#if !defined(__MODEL__)
+#  error "FIXME - MCS51 __MODEL__"
+#elif ((__MODEL__) == 1)
+#  define ACC_MM_SMALL          1
+#elif ((__MODEL__) == 2)
+#  define ACC_MM_LARGE          1
+#elif ((__MODEL__) == 3)
+#  define ACC_MM_TINY           1
+#elif ((__MODEL__) == 4)
+#  define ACC_MM_XTINY          1
+#elif ((__MODEL__) == 5)
+#  define ACC_MM_XSMALL         1
+#else
+#  error "FIXME - MCS51 __MODEL__"
+#endif
+
 #else
 
 #  define ACC_MM_FLAT           1
diff --git a/src/acc/acclib/hsread.ch b/src/acc/acclib/hsread.ch
new file mode 100644
index 00000000..cf7b5260
--- /dev/null
+++ b/src/acc/acclib/hsread.ch
@@ -0,0 +1,97 @@
+/* ACC -- Automatic Compiler Configuration
+
+   Copyright (C) 1996-2004 Markus Franz Xaver Johannes Oberhumer
+   All Rights Reserved.
+
+   This software is a copyrighted work licensed under the terms of
+   the GNU General Public License. Please consult the file "ACC_LICENSE"
+   for details.
+
+   Markus F.X.J. Oberhumer
+   <markus@oberhumer.com>
+   http://www.oberhumer.com/
+ */
+
+
+#define __ACCLIB_HSREAD_CH_INCLUDED 1
+#if !defined(ACCLIB_PUBLIC)
+#  define ACCLIB_PUBLIC(r,f)    r __ACCLIB_FUNCNAME(f)
+#endif
+
+
+/***********************************************************************
+// huge pointer layer - safe read/write
+// handles partial pipe writes and interrupted system calls
+************************************************************************/
+
+ACCLIB_PUBLIC(long, acc_safe_hread) (int fd, acc_hvoid_p buf, long size)
+{
+    acc_hbyte_p b = (acc_hbyte_p) buf;
+    long l = 0;
+    int saved_errno;
+
+    saved_errno = errno;
+    while (l < size)
+    {
+        long n = size - l;
+#if (ACC_HAVE_MM_HUGE_PTR)
+#  define __ACCLIB_REQUIRE_HREAD_CH 1
+        errno = 0; n = acc_hread(fd, b, n);
+#elif (ACC_OS_DOS32) && defined(__DJGPP__)
+        errno = 0; n = _read(fd, b, n);
+#else
+        errno = 0; n = read(fd, b, n);
+#endif
+        if (n == 0)
+            break;
+        if (n < 0) {
+#if defined(EINTR)
+            if (errno == (EINTR)) continue;
+#endif
+            if (errno == 0) errno = 1;
+            return l;
+        }
+        b += n; l += n;
+    }
+    errno = saved_errno;
+    return l;
+}
+
+
+ACCLIB_PUBLIC(long, acc_safe_hwrite) (int fd, const acc_hvoid_p buf, long size)
+{
+    const acc_hbyte_p b = (const acc_hbyte_p) buf;
+    long l = 0;
+    int saved_errno;
+
+    saved_errno = errno;
+    while (l < size)
+    {
+        long n = size - l;
+#if (ACC_HAVE_MM_HUGE_PTR)
+#  define __ACCLIB_REQUIRE_HREAD_CH 1
+        errno = 0; n = acc_hwrite(fd, b, n);
+#elif (ACC_OS_DOS32) && defined(__DJGPP__)
+        errno = 0; n = _write(fd, b, n);
+#else
+        errno = 0; n = write(fd, b, n);
+#endif
+        if (n == 0)
+            break;
+        if (n < 0) {
+#if defined(EINTR)
+            if (errno == (EINTR)) continue;
+#endif
+            if (errno == 0) errno = 1;
+            return l;
+        }
+        b += n; l += n;
+    }
+    errno = saved_errno;
+    return l;
+}
+
+
+/*
+vi:ts=4:et
+*/
diff --git a/src/acc/acclib/rdtsc.ch b/src/acc/acclib/rdtsc.ch
new file mode 100644
index 00000000..ede2aacf
--- /dev/null
+++ b/src/acc/acclib/rdtsc.ch
@@ -0,0 +1,127 @@
+/* ACC -- Automatic Compiler Configuration
+
+   Copyright (C) 1996-2004 Markus Franz Xaver Johannes Oberhumer
+   All Rights Reserved.
+
+   This software is a copyrighted work licensed under the terms of
+   the GNU General Public License. Please consult the file "ACC_LICENSE"
+   for details.
+
+   Markus F.X.J. Oberhumer
+   <markus@oberhumer.com>
+   http://www.oberhumer.com/
+ */
+
+
+#define __ACCLIB_RDTSC_CH_INCLUDED 1
+#if !defined(ACCLIB_PUBLIC)
+#  define ACCLIB_PUBLIC(r,f)    r __ACCLIB_FUNCNAME(f)
+#endif
+
+#if defined(acc_int32e_t)
+
+
+/*************************************************************************
+// read TSC
+**************************************************************************/
+
+ACCLIB_PUBLIC(int, acc_tsc_read) (acc_uint32e_t* t)
+{
+#if ((ACC_ARCH_AMD64 || ACC_ARCH_IA32) && ACC_CC_GNUC)
+    __asm__ __volatile__(
+        "clc \n" ".byte 0x0f, 0x31\n"
+        "movl %%eax,(%0)\n" "movl %%edx,4(%0)\n"
+#  if (ACC_CC_GNUC >= 0x020000ul)
+        : : "r" (t) : "cc", "memory", "eax", "edx"
+#  else
+        : : "r" (t) : "ax", "dx"
+#  endif
+    );
+    return 0;
+#elif (ACC_ARCH_IA32 && ACC_CC_INTELC) && defined(__linux__)
+    __asm__ __volatile__(
+        "clc \n" ".byte 0x0f, 0x31\n"
+        "movl %%eax,(%0)\n" "movl %%edx,4(%0)\n"
+        : : "r" (t) : "memory", "eax", "edx"
+    );
+    return 0;
+#elif (ACC_ARCH_IA32 && (ACC_OS_DOS32 || ACC_OS_WIN32) && (ACC_CC_DMC || ACC_CC_INTELC || ACC_CC_MSC))
+    ACC_UNUSED(t);
+    __asm {
+        mov ecx, t
+        clc
+#  if (ACC_CC_MSC && (_MSC_VER < 1200))
+        _emit 0x0f
+        _emit 0x31
+#  else
+        rdtsc
+#  endif
+        mov [ecx], eax
+        mov [ecx+4], edx
+    }
+    return 0;
+#else
+    t[0] = t[1] = 0;
+    return -1;
+#endif
+}
+
+
+/*************************************************************************
+// read and add TSC
+**************************************************************************/
+
+ACCLIB_PUBLIC(int, acc_tsc_read_add) (acc_uint32e_t* t)
+{
+#if ((ACC_ARCH_AMD64 || ACC_ARCH_IA32) && ACC_CC_GNUC)
+    __asm__ __volatile__(
+        "clc \n" ".byte 0x0f, 0x31\n"
+        "addl %%eax,(%0)\n" "adcl $0,%%edx\n" "addl %%edx,4(%0)\n"
+#  if (ACC_CC_GNUC >= 0x020000ul)
+        : : "r" (t) : "cc", "memory", "eax", "edx"
+#  else
+        : : "r" (t) : "ax", "dx"
+#  endif
+    );
+    return 0;
+#elif (ACC_ARCH_IA32 && ACC_CC_INTELC) && defined(__linux__)
+    __asm__ __volatile__(
+        "clc \n" ".byte 0x0f, 0x31\n"
+        "addl %%eax,(%0)\n" "adcl $0,%%edx\n" "addl %%edx,4(%0)\n"
+        : : "r" (t) : "memory", "eax", "edx"
+    );
+    return 0;
+#elif (ACC_ARCH_IA32 && (ACC_OS_DOS32 || ACC_OS_WIN32) && (ACC_CC_DMC || ACC_CC_INTELC || ACC_CC_MSC))
+    ACC_UNUSED(t);
+    __asm {
+        mov ecx, t
+        clc
+#  if (ACC_CC_MSC && (_MSC_VER < 1200))
+        _emit 0x0f
+        _emit 0x31
+#  else
+        rdtsc
+#  endif
+        add [ecx], eax
+        adc edx, 0
+        add [ecx+4], edx
+    }
+    return 0;
+#else
+    acc_uint32e_t v[2];
+    int r;
+    r = acc_tsc_read(v);
+    t[0] += v[0];
+    if (t[0] < v[0]) t[1] += 1;
+    t[1] += v[1];
+    return r;
+#endif
+}
+
+
+#endif /* defined(acc_int32e_t) */
+
+
+/*
+vi:ts=4:et
+*/