diff --git a/apc_cache.c b/apc_cache.c
index baa19ce..142f0d4 100644
--- a/apc_cache.c
+++ b/apc_cache.c
@@ -1100,7 +1100,7 @@ PHP_APCU_API zend_bool apc_cache_info(zval *info, apc_cache_t *cache, zend_bool
 		add_assoc_long(info, "start_time", cache->header->stime);
 		array_add_double(info, apc_str_mem_size, (double) cache->header->mem_size);
 
-#if APC_MMAP
+#ifdef APC_MMAP
 		add_assoc_stringl(info, "memory_type", "mmap", sizeof("mmap")-1);
 #else
 		add_assoc_stringl(info, "memory_type", "IPC shared", sizeof("IPC shared")-1);
diff --git a/apc_globals.h b/apc_globals.h
index c0a4436..8ad84a3 100644
--- a/apc_globals.h
+++ b/apc_globals.h
@@ -44,7 +44,7 @@ ZEND_BEGIN_MODULE_GLOBALS(apcu)
 	zend_long ttl;               /* parameter to apc_cache_create */
 	zend_long smart;             /* smart value */
 
-#if APC_MMAP
+#ifdef APC_MMAP
 	char *mmap_file_mask;   /* mktemp-style file-mask to pass to mmap */
 #endif
 
diff --git a/apc_mmap.c b/apc_mmap.c
index 9337d45..faabf93 100644
--- a/apc_mmap.c
+++ b/apc_mmap.c
@@ -29,7 +29,7 @@
 #include "apc_mmap.h"
 #include "apc_lock.h"
 
-#if APC_MMAP
+#ifdef APC_MMAP
 
 #include <fcntl.h>
 #include <sys/types.h>
diff --git a/apc_mmap.h b/apc_mmap.h
index 16ababc..30eec9f 100644
--- a/apc_mmap.h
+++ b/apc_mmap.h
@@ -35,7 +35,7 @@
 
 /* Wrapper functions for shared memory mapped files */
 
-#if APC_MMAP
+#ifdef APC_MMAP
 apc_segment_t apc_mmap(char *file_mask, size_t size);
 void apc_unmap(apc_segment_t* segment);
 #endif
diff --git a/apc_sma.c b/apc_sma.c
index 751c325..b0bbbc8 100644
--- a/apc_sma.c
+++ b/apc_sma.c
@@ -299,7 +299,7 @@ PHP_APCU_API void apc_sma_init(apc_sma_t* sma, void** data, apc_sma_expunge_f ex
 	sma->expunge = expunge;
 	sma->data = data;
 
-#if APC_MMAP
+#ifdef APC_MMAP
 	/*
 	 * I don't think multiple anonymous mmaps makes any sense
 	 * so force sma_numseg to 1 in this case
@@ -324,7 +324,7 @@ PHP_APCU_API void apc_sma_init(apc_sma_t* sma, void** data, apc_sma_expunge_f ex
 		block_t     *first, *empty, *last;
 		void*       shmaddr;
 
-#if APC_MMAP
+#ifdef APC_MMAP
 		sma->segs[i] = apc_mmap(mask, sma->size);
 		if(sma->num != 1)
 			memcpy(&mask[strlen(mask)-6], "XXXXXX", 6);
@@ -388,7 +388,7 @@ PHP_APCU_API void apc_sma_detach(apc_sma_t* sma) {
 	sma->initialized = 0;
 
 	for (i = 0; i < sma->num; i++) {
-#if APC_MMAP
+#ifdef APC_MMAP
 		apc_unmap(&sma->segs[i]);
 #else
 		apc_shm_detach(&sma->segs[i]);
diff --git a/config.m4 b/config.m4
index c14402c..47edf36 100644
--- a/config.m4
+++ b/config.m4
@@ -10,39 +10,26 @@ PHP_ARG_ENABLE([apcu-rwlocks],
   [yes],
   [no])
 
-AC_MSG_CHECKING(if APCu should be built in debug mode)
-AC_ARG_ENABLE([apcu-debug],
+PHP_ARG_ENABLE([apcu-debug],
+  [if APCu should be built in debug mode],
   [AS_HELP_STRING([--enable-apcu-debug],
     [Enable APCu debugging])],
-  [PHP_APCU_DEBUG=$enableval],
-  [PHP_APCU_DEBUG=no])
-AC_MSG_RESULT($PHP_APCU_DEBUG)
+  [no],
+  [no])
 
-AC_MSG_CHECKING(if APCu should clear on SIGUSR1)
-AC_ARG_ENABLE([apcu-clear-signal],
+PHP_ARG_ENABLE([apcu-clear-signal],
+  [if APCu should clear on SIGUSR1],
   [AS_HELP_STRING([--enable-apcu-clear-signal],
     [Enable SIGUSR1 clearing handler])],
-[
-  AC_DEFINE(APC_CLEAR_SIGNAL, 1, [ ])
-  AC_MSG_RESULT(yes)
-],
-[
-  AC_MSG_RESULT(no)
-])
-
-PHP_APCU_MMAP=yes
-AC_MSG_CHECKING([if APCu will use mmap (or shm)])
-AC_ARG_ENABLE([apcu-mmap],
+  [no],
+  [no])
+
+PHP_ARG_ENABLE([apcu-mmap],
+  [if APCu should use mmap instead of shm],
   [AS_HELP_STRING([--disable-apcu-mmap],
     [Disable mmap, falls back on shm])],
-[
-  if test "x$enableval" = "xno"; then
-    PHP_APCU_MMAP=no
-  else
-    PHP_APCU_MMAP=yes
-  fi
-])
-AC_MSG_RESULT($PHP_APCU_MMAP)
+  [yes],
+  [no])
 
 PHP_ARG_ENABLE([apcu-spinlocks],
   [if APCu should utilize spinlocks before flocks],
@@ -51,7 +38,37 @@ PHP_ARG_ENABLE([apcu-spinlocks],
   [no],
   [no])
 
+PHP_ARG_ENABLE([valgrind-checks],
+  [whether to enable Valgrind-based memory checks],
+  [AS_HELP_STRING([--disable-valgrind-checks],
+    [Disable Valgrind-based memory checks])],
+  [yes],
+  [no])
+
+PHP_ARG_ENABLE([coverage],
+  [whether to include code coverage symbols],
+  [AS_HELP_STRING([--enable-coverage],
+    [Include code coverage symbols (DEVELOPERS ONLY!!)])],
+  [no],
+  [no])
+
 if test "$PHP_APCU" != "no"; then
+  AS_VAR_IF([PHP_APCU_DEBUG], [no], [],
+    [AC_DEFINE([APC_DEBUG], [1],
+      [Define to 1 if APCu debugging mode is enabled.])])
+
+  AS_VAR_IF([PHP_APCU_CLEAR_SIGNAL], [no], [],
+    [AC_DEFINE([APC_CLEAR_SIGNAL], [1],
+      [Define to 1 if SIGUSR1 clearing handler is enabled.])])
+
+  AS_VAR_IF([PHP_APCU_MMAP], [no], [],
+    [AC_DEFINE([APC_MMAP], [1],
+      [Define to 1 if APCu uses mmap instead of shm.])])
+
+  AS_VAR_IF([PHP_VALGRIND_CHECKS], [no], [],
+    [AC_CHECK_HEADERS([valgrind/memcheck.h], [],
+      [AC_MSG_NOTICE([Valgrind-based memory checks are disabled.])])])
+
   AS_VAR_IF([PHP_APCU_RWLOCKS], [no], [], [
     AC_CACHE_CHECK([whether the target compiler supports builtin atomics],
       [PHP_cv_APCU_GCC_ATOMICS],
@@ -65,14 +82,6 @@ if test "$PHP_APCU" != "no"; then
       [AC_MSG_FAILURE([Compiler does not support atomics])])
   ])
 
-  if test "$PHP_APCU_DEBUG" != "no"; then
-    AC_DEFINE(APC_DEBUG, 1, [ ])
-  fi
-
-  if test "$PHP_APCU_MMAP" != "no"; then
-    AC_DEFINE(APC_MMAP, 1, [ ])
-  fi
-
   if test "$PHP_APCU_RWLOCKS" != "no"; then
       orig_LIBS="$LIBS"
       LIBS="$LIBS -lpthread"
@@ -192,16 +201,6 @@ if test "$PHP_APCU" != "no"; then
 
   AC_CHECK_FUNCS(sigaction)
 
-  AC_ARG_ENABLE([valgrind-checks],
-    [AS_HELP_STRING([--disable-valgrind-checks],
-      [Disable Valgrind based memory checks])],
-    [PHP_APCU_VALGRIND=no],
-    [
-    PHP_APCU_VALGRIND=yes
-    AC_CHECK_HEADER(valgrind/memcheck.h,
-      [AC_DEFINE([HAVE_VALGRIND_MEMCHECK_H],1, [enable valgrind memchecks])])
-    ])
-
   for i in -Wall -Wextra -Wno-unused-parameter; do
     AX_CHECK_COMPILE_FLAG([$i], [APCU_CFLAGS="$APCU_CFLAGS $i"])
   done
@@ -225,13 +224,6 @@ if test "$PHP_APCU" != "no"; then
   AC_DEFINE(HAVE_APCU, 1, [ ])
 fi
 
-PHP_ARG_ENABLE([coverage],
-  [whether to include code coverage symbols],
-  [AS_HELP_STRING([--enable-coverage],
-    [Include code coverage symbols (DEVELOPERS ONLY!!)])],
-  [no],
-  [no])
-
 if test "$PHP_COVERAGE" = "yes"; then
 
   if test "$GCC" != "yes"; then
diff --git a/php_apc.c b/php_apc.c
index 6193d89..d00b5f3 100644
--- a/php_apc.c
+++ b/php_apc.c
@@ -94,7 +94,7 @@ static void php_apc_init_globals(zend_apcu_globals* apcu_globals)
 static PHP_INI_MH(OnUpdateShmSegments) /* {{{ */
 {
 	zend_long shm_segments = ZEND_STRTOL(new_value->val, NULL, 10);
-#if APC_MMAP
+#ifdef APC_MMAP
 	if (shm_segments != 1) {
 		php_error_docref(NULL, E_WARNING, "apc.shm_segments setting ignored in MMAP mode");
 	}
@@ -139,7 +139,7 @@ STD_PHP_INI_ENTRY("apc.entries_hint",   "4096", PHP_INI_SYSTEM, OnUpdateLong,
 STD_PHP_INI_ENTRY("apc.gc_ttl",         "3600", PHP_INI_SYSTEM, OnUpdateLong,              gc_ttl,           zend_apcu_globals, apcu_globals)
 STD_PHP_INI_ENTRY("apc.ttl",            "0",    PHP_INI_SYSTEM, OnUpdateLong,              ttl,              zend_apcu_globals, apcu_globals)
 STD_PHP_INI_ENTRY("apc.smart",          "0",    PHP_INI_SYSTEM, OnUpdateLong,              smart,            zend_apcu_globals, apcu_globals)
-#if APC_MMAP
+#ifdef APC_MMAP
 STD_PHP_INI_ENTRY("apc.mmap_file_mask",  NULL,  PHP_INI_SYSTEM, OnUpdateString,            mmap_file_mask,   zend_apcu_globals, apcu_globals)
 #endif
 STD_PHP_INI_BOOLEAN("apc.enable_cli",   "0",    PHP_INI_SYSTEM, OnUpdateBool,              enable_cli,       zend_apcu_globals, apcu_globals)
@@ -168,7 +168,7 @@ static PHP_MINFO_FUNCTION(apcu)
 #else
 	php_info_print_table_row(2, "APCu Debugging", "Disabled");
 #endif
-#if APC_MMAP
+#ifdef APC_MMAP
 	php_info_print_table_row(2, "MMAP Support", "Enabled");
 	php_info_print_table_row(2, "MMAP File Mask", APCG(mmap_file_mask));
 #else
@@ -235,7 +235,7 @@ static PHP_MINIT_FUNCTION(apcu)
 	if (APCG(enabled)) {
 
 		if (!APCG(initialized)) {
-#if APC_MMAP
+#ifdef APC_MMAP
 			char *mmap_file_mask = APCG(mmap_file_mask);
 #else
 			char *mmap_file_mask = NULL;