diff --git a/Makefile b/Makefile
index 66a8411eb7..c2e1fba788 100644
--- a/Makefile
+++ b/Makefile
@@ -184,7 +184,7 @@ ifeq ($(findstring -Wall,$(_ASTCFLAGS) $(ASTCFLAGS)),)
   _ASTCFLAGS+=-Wall
 endif
 
-_ASTCFLAGS+=-Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations $(AST_NESTED_FUNCTIONS) $(DEBUG)
+_ASTCFLAGS+=-Wstrict-prototypes -Wmissing-prototypes -Wmissing-declarations $(AST_NESTED_FUNCTIONS) $(AST_CLANG_BLOCKS) $(DEBUG)
 ADDL_TARGETS=
 
 ifeq ($(AST_DEVMODE),yes)
@@ -931,7 +931,7 @@ nmenuselect: menuselect/nmenuselect menuselect-tree menuselect.makeopts
 	-@menuselect/nmenuselect menuselect.makeopts && (echo "menuselect changes saved!"; rm -f channels/h323/Makefile.ast main/asterisk) || echo "menuselect changes NOT saved!"
 
 # options for make in menuselect/
-MAKE_MENUSELECT=CC="$(BUILD_CC)" CXX="" LD="" AR="" RANLIB="" \
+MAKE_MENUSELECT=CC="$(CC)" CXX="$(CXX)" LD="" AR="" RANLIB="" \
 		CFLAGS="$(BUILD_CFLAGS)" LDFLAGS="$(BUILD_LDFLAGS)" \
 		$(MAKE) -C menuselect CONFIGURE_SILENT="--silent"
 
diff --git a/configure b/configure
index 3a681b564d..c7c0608c92 100755
--- a/configure
+++ b/configure
@@ -1,5 +1,5 @@
 #! /bin/sh
-# From configure.ac Revision: 431092 .
+# From configure.ac Revision: 432281 .
 # Guess values for system-dependent variables and create Makefiles.
 # Generated by GNU Autoconf 2.69 for asterisk trunk.
 #
@@ -687,6 +687,8 @@ PBX_RTLD_NOLOAD
 PBX_GLOB_BRACE
 PBX_GLOB_NOMAGIC
 AST_RPATH
+AST_CLANG_BLOCKS
+AST_CLANG_BLOCKS_LIBS
 AST_NESTED_FUNCTIONS
 AST_NATIVE_ARCH
 AST_SHADOW_WARNINGS
@@ -17305,7 +17307,7 @@ fi
 
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking for -Wtrampolines support" >&5
 $as_echo_n "checking for -Wtrampolines support... " >&6; }
-if $(${CC} -Wtrampolines -S -o /dev/null -xc /dev/null > /dev/null 2>&1); then
+if $(${CC} -Wtrampolines -Werror -S -o /dev/null -xc /dev/null > /dev/null 2>&1); then
 	{ $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
 $as_echo "yes" >&6; }
 	AST_TRAMPOLINES=-Wtrampolines
@@ -17374,11 +17376,29 @@ $as_echo "no" >&6; }
 fi
 
 
-{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for -fnested-functions" >&5
-$as_echo_n "checking for -fnested-functions... " >&6; }
 cat confdefs.h - <<_ACEOF >conftest.$ac_ext
 /* end confdefs.h.  */
 
+int
+main ()
+{
+
+		#if defined(__clang__)
+		choke
+		#endif
+
+  ;
+  return 0;
+}
+
+_ACEOF
+if ac_fn_c_try_link "$LINENO"; then :
+
+				{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for gcc -fnested-functions" >&5
+$as_echo_n "checking for gcc -fnested-functions... " >&6; }
+		cat confdefs.h - <<_ACEOF >conftest.$ac_ext
+/* end confdefs.h.  */
+
 int
 main ()
 {
@@ -17390,16 +17410,41 @@ _ACEOF
 if ac_fn_c_try_compile "$LINENO"; then :
   { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
 $as_echo "no" >&6; }
-	AST_NESTED_FUNCTIONS=
+			AST_NESTED_FUNCTIONS=
 else
-  { $as_echo "$as_me:${as_lineno-$LINENO}: result: required" >&5
-$as_echo "required" >&6; }
-	AST_NESTED_FUNCTIONS=-fnested-functions
+  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+			AST_NESTED_FUNCTIONS=-fnested-functions
 
 fi
 rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
 
 
+else
+
+		{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for clang -fblocks" >&5
+$as_echo_n "checking for clang -fblocks... " >&6; }
+		if test "`echo "int main(){return ^{return 42;}();}" | ${CC} -o /dev/null -fblocks -x c - 2>&1`" = ""; then
+			AST_CLANG_BLOCKS_LIBS=""
+			AST_CLANG_BLOCKS="-Wno-unknown-warning-option -fblocks"
+			{ $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+		elif test "`echo "int main(){return ^{return 42;}();}" | ${CC} -o /dev/null -fblocks -x c -lBlocksRuntime - 2>&1`" = ""; then
+			AST_CLANG_BLOCKS_LIBS="-lBlocksRuntime"
+			AST_CLANG_BLOCKS="-fblocks"
+			{ $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
+$as_echo "yes" >&6; }
+		else
+			as_fn_error $? "\"BlocksRuntime is required for clang\"" "$LINENO" 5
+		fi
+
+
+
+
+fi
+rm -f core conftest.err conftest.$ac_objext \
+    conftest$ac_exeext conftest.$ac_ext
+
 # Check whether --enable-rpath was given.
 if test "${enable_rpath+set}" = set; then :
   enableval=$enable_rpath; case "${enableval}" in
diff --git a/configure.ac b/configure.ac
index de90e6a324..edb4322b12 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1078,7 +1078,7 @@ fi
 AC_SUBST(AST_DECLARATION_AFTER_STATEMENT)
 
 AC_MSG_CHECKING(for -Wtrampolines support)
-if $(${CC} -Wtrampolines -S -o /dev/null -xc /dev/null > /dev/null 2>&1); then
+if $(${CC} -Wtrampolines -Werror -S -o /dev/null -xc /dev/null > /dev/null 2>&1); then
 	AC_MSG_RESULT(yes)
 	AST_TRAMPOLINES=-Wtrampolines
 else
@@ -1133,16 +1133,41 @@ fi
 AC_SUBST(AST_NATIVE_ARCH)
 
 dnl Nested functions required for RAII implementation
-AC_MSG_CHECKING(for -fnested-functions)
-AC_COMPILE_IFELSE(
-	dnl Prototype needed due to http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36774
-	[AC_LANG_PROGRAM([], [auto void foo(void); void foo(void) {}])],
-	AC_MSG_RESULT(no)
-	[AST_NESTED_FUNCTIONS=],
-	AC_MSG_RESULT(required)
-	[AST_NESTED_FUNCTIONS=-fnested-functions]
+AC_LINK_IFELSE(
+	[AC_LANG_PROGRAM([], [
+		#if defined(__clang__)
+		choke
+		#endif
+		])
+	],[
+		dnl Nested functions required for RAII implementation
+		AC_MSG_CHECKING(for gcc -fnested-functions)
+		AC_COMPILE_IFELSE(
+			dnl Prototype needed due to http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36774
+			[AC_LANG_PROGRAM([], [auto void foo(void); void foo(void) {}])],
+			AC_MSG_RESULT(no)
+			[AST_NESTED_FUNCTIONS=],
+			AC_MSG_RESULT(yes)
+			[AST_NESTED_FUNCTIONS=-fnested-functions]
+		)
+		AC_SUBST(AST_NESTED_FUNCTIONS)
+	],[
+		AC_MSG_CHECKING(for clang -fblocks)
+		if test "`echo "int main(){return ^{return 42;}();}" | ${CC} -o /dev/null -fblocks -x c - 2>&1`" = ""; then
+			[AST_CLANG_BLOCKS_LIBS=""]
+			[AST_CLANG_BLOCKS="-Wno-unknown-warning-option -fblocks"]
+			AC_MSG_RESULT(yes)
+		elif test "`echo "int main(){return ^{return 42;}();}" | ${CC} -o /dev/null -fblocks -x c -lBlocksRuntime - 2>&1`" = ""; then
+			[AST_CLANG_BLOCKS_LIBS="-lBlocksRuntime"]
+			[AST_CLANG_BLOCKS="-fblocks"]
+			AC_MSG_RESULT(yes)
+		else
+			AC_MSG_ERROR("BlocksRuntime is required for clang")
+		fi
+		AC_SUBST(AST_CLANG_BLOCKS_LIBS)
+		AC_SUBST(AST_CLANG_BLOCKS)
+	]
 )
-AC_SUBST(AST_NESTED_FUNCTIONS)
 
 dnl Check to see if rpath should be set in LDFLAGS
 AC_ARG_ENABLE(rpath,
diff --git a/include/asterisk/inline_api.h b/include/asterisk/inline_api.h
index 5f6911d369..d76dfa0a52 100644
--- a/include/asterisk/inline_api.h
+++ b/include/asterisk/inline_api.h
@@ -25,12 +25,14 @@
   Small API functions that are candidates for inlining need to be specially
   declared and defined, to ensure that the 'right thing' always happens.
   For example:
-  	- there must _always_ be a non-inlined version of the function
+	- there must _always_ be a non-inlined version of the function
 	available for modules compiled out of the tree to link to
 	- references to a function that cannot be inlined (for any
 	reason that the compiler deems proper) must devolve into an
 	'extern' reference, instead of 'static', so that multiple
-	copies of the function body are not built in different modules
+	copies of the function body are not built in different modules.
+	However, since this doesn't work for clang, we go with 'static'
+	anyway and hope for the best!
 	- when LOW_MEMORY is defined, inlining should be disabled
 	completely, even if the compiler is configured to support it
 
@@ -46,8 +48,12 @@
 #if !defined(LOW_MEMORY) && !defined(DISABLE_INLINE)
 
 #if !defined(AST_API_MODULE)
+#if defined(__clang__)
+#define AST_INLINE_API(hdr, body) static hdr; static inline hdr body
+#else /* if defined(__clang__) */
 #define AST_INLINE_API(hdr, body) hdr; extern inline hdr body
-#else
+#endif
+#else /* if !defined(AST_API_MODULE) */
 #define AST_INLINE_API(hdr, body) hdr; hdr body
 #endif
 
diff --git a/include/asterisk/utils.h b/include/asterisk/utils.h
index a0e7cb6bf5..1dc351d0ac 100644
--- a/include/asterisk/utils.h
+++ b/include/asterisk/utils.h
@@ -1005,12 +1005,33 @@ char *ast_utils_which(const char *binary, char *fullpath, size_t fullpath_size);
  * }
  * \endcode
  */
-#define RAII_VAR(vartype, varname, initval, dtor) \
-    /* Prototype needed due to http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36774 */ \
-    auto void _dtor_ ## varname (vartype * v); \
-    void _dtor_ ## varname (vartype * v) { dtor(*v); } \
+
+#if defined(__clang__)
+
+#if defined(__has_feature) && __has_feature(blocks)
+typedef void (^_raii_cleanup_block_t)(void);
+static inline void _raii_cleanup_block(_raii_cleanup_block_t *b) { (*b)(); }
+
+#define RAII_VAR(vartype, varname, initval, dtor)                                                                \
+    _raii_cleanup_block_t _raii_cleanup_ ## varname __attribute__((cleanup(_raii_cleanup_block),unused)) = NULL; \
+    vartype varname = initval;                                                                                   \
+    _raii_cleanup_ ## varname = ^{ dtor(varname); }
+
+#else
+	#error "CLANG must support the 'blocks' feature to compile Asterisk."
+#endif /* #if defined(__has_feature) && __has_feature(blocks) */
+
+#elif defined(__GNUC__)
+
+#define RAII_VAR(vartype, varname, initval, dtor)                              \
+    auto void _dtor_ ## varname (vartype * v);                                 \
+    void _dtor_ ## varname (vartype * v) { dtor(*v); }                         \
     vartype varname __attribute__((cleanup(_dtor_ ## varname))) = (initval)
 
+#else
+    #error "Cannot compile Asterisk: unknown and unsupported compiler."
+#endif /* #if __GNUC__ */
+
 /*!
  * \brief Asterisk wrapper around crypt(3).
  *
diff --git a/main/Makefile b/main/Makefile
index 0fa219297f..0a63c01a04 100644
--- a/main/Makefile
+++ b/main/Makefile
@@ -40,6 +40,7 @@ AST_LIBS+=$(JANSSON_LIB)
 AST_LIBS+=$(URIPARSER_LIB)
 AST_LIBS+=$(UUID_LIB)
 AST_LIBS+=$(CRYPT_LIB)
+AST_LIBS+=$(AST_CLANG_BLOCKS_LIBS)
 
 ifneq ($(findstring $(OSARCH), linux-gnu uclinux linux-uclibc kfreebsd-gnu),)
   ifneq ($(findstring LOADABLE_MODULES,$(MENUSELECT_CFLAGS)),)
diff --git a/makeopts.in b/makeopts.in
index a0faaee463..96b031bdd2 100644
--- a/makeopts.in
+++ b/makeopts.in
@@ -109,6 +109,8 @@ AST_TRAMPOLINES=@AST_TRAMPOLINES@
 AST_NO_STRICT_OVERFLOW=@AST_NO_STRICT_OVERFLOW@
 AST_SHADOW_WARNINGS=@AST_SHADOW_WARNINGS@
 AST_NESTED_FUNCTIONS=@AST_NESTED_FUNCTIONS@
+AST_CLANG_BLOCKS=@AST_CLANG_BLOCKS@
+AST_CLANG_BLOCKS_LIBS=@AST_CLANG_BLOCKS_LIBS@
 AST_RPATH=@AST_RPATH@
 AST_FORTIFY_SOURCE=@AST_FORTIFY_SOURCE@
 AST_MARCH_NATIVE=@AST_MARCH_NATIVE@