diff -ur spack-src.org/CMakeLists.txt spack-src/CMakeLists.txt
--- spack-src.org/CMakeLists.txt	2020-03-26 16:38:53.358339744 +0900
+++ spack-src/CMakeLists.txt	2020-03-26 16:44:04.581014766 +0900
@@ -184,6 +184,9 @@
 CHECK_INCLUDE_FILES(malloc.h HAVE_MALLOC_H)
 CHECK_INCLUDE_FILES(memory.h HAVE_MEMORY_H)
 INCLUDE_DIRECTORIES(${CMAKE_CURRENT_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR})
+include(CheckSymbolExists)
+check_symbol_exists(__clear_cache "" CLEAR_CACHE_DEFINED)
+message(STATUS "Clear cache defined is ${CLEAR_CACHE_DEFINED}")
 
 set (NO_DISASSEMBLER TRUE)
 if (ENABLE_DISASSEMBLY)
diff -ur spack-src.org/arm6.c spack-src/arm6.c
--- spack-src.org/arm6.c	2020-03-26 16:38:53.358339744 +0900
+++ spack-src/arm6.c	2020-03-26 16:45:20.428978615 +0900
@@ -1524,22 +1524,9 @@
 }
 
 
-/* Clear the instruction cache from `beg' to `end'.  This makes an
-   inline system call to SYS_cacheflush.  */
-#define CLEAR_INSN_CACHE(BEG, END)                                      \
-{                                                                       \
-  register unsigned long _beg __asm ("a1") = (unsigned long) (BEG);     \
-  register unsigned long _end __asm ("a2") = (unsigned long) (END);     \
-  register unsigned long _flg __asm ("a3") = 0;                         \
-  __asm __volatile ("swi 0x9f0002               @ sys_cacheflush"       \
-                    : "=r" (_beg)                                       \
-                    : "0" (_beg), "r" (_end), "r" (_flg));              \
-}
-/*
- *  Cache flush code grabbed from a Dec 1999 posting on libc-hacker 
- *  mailing list
- */
-extern void __clear_cache(char*, char *);
+#ifndef CLEAR_CACHE_DEFINED
+extern void __clear_cache(void *, void *);
+#endif
 
 static void
 arm6_flush(void *base, void *limit)
diff -ur spack-src.org/arm6_rt.c spack-src/arm6_rt.c
--- spack-src.org/arm6_rt.c	2020-03-26 16:38:53.358339744 +0900
+++ spack-src/arm6_rt.c	2020-03-26 16:48:18.927720543 +0900
@@ -109,22 +109,9 @@
     }
 }
 
-/* Clear the instruction cache from `beg' to `end'.  This makes an
-   inline system call to SYS_cacheflush.  */
-#define CLEAR_INSN_CACHE(BEG, END)                                      \
-{                                                                       \
-  register unsigned long _beg __asm ("a1") = (unsigned long) (BEG);     \
-  register unsigned long _end __asm ("a2") = (unsigned long) (END);     \
-  register unsigned long _flg __asm ("a3") = 0;                         \
-  __asm __volatile ("swi 0x9f0002               @ sys_cacheflush"       \
-                    : "=r" (_beg)                                       \
-                    : "0" (_beg), "r" (_end), "r" (_flg));              \
-}
-/*
- *  Cache flush code grabbed from a Dec 1999 posting on libc-hacker 
- *  mailing list
- */
-extern void __clear_cache(char*, char *);
+#ifndef CLEAR_CACHE_DEFINED
+extern void __clear_cache(void *, void *);
+#endif
 
 static void
 arm6_flush(void *base, void *limit)
diff -ur spack-src.org/arm8.c spack-src/arm8.c
--- spack-src.org/arm8.c	2020-03-26 16:38:53.358339744 +0900
+++ spack-src/arm8.c	2020-03-26 16:49:38.386063473 +0900
@@ -1524,22 +1524,9 @@
 }
 
 
-/* Clear the instruction cache from `beg' to `end'.  This makes an
-   inline system call to SYS_cacheflush.  */
-#define CLEAR_INSN_CACHE(BEG, END)                                      \
-{                                                                       \
-  register unsigned long _beg __asm ("a1") = (unsigned long) (BEG);     \
-  register unsigned long _end __asm ("a2") = (unsigned long) (END);     \
-  register unsigned long _flg __asm ("a3") = 0;                         \
-  __asm __volatile ("swi 0x9f0002               @ sys_cacheflush"       \
-                    : "=r" (_beg)                                       \
-                    : "0" (_beg), "r" (_end), "r" (_flg));              \
-}
-/*
- *  Cache flush code grabbed from a Dec 1999 posting on libc-hacker 
- *  mailing list
- */
-extern void __clear_cache(char*, char *);
+#ifndef CLEAR_CACHE_DEFINED
+extern void __clear_cache(void *, void *);
+#endif
 
 static void
 arm8_flush(void *base, void *limit)
diff -ur spack-src.org/arm8_rt.c spack-src/arm8_rt.c
--- spack-src.org/arm8_rt.c	2020-03-26 16:38:53.358339744 +0900
+++ spack-src/arm8_rt.c	2020-03-26 16:50:37.902312532 +0900
@@ -109,22 +109,9 @@
     }
 }
 
-/* Clear the instruction cache from `beg' to `end'.  This makes an
-   inline system call to SYS_cacheflush.  */
-#define CLEAR_INSN_CACHE(BEG, END)                                      \
-{                                                                       \
-  register unsigned long _beg __asm ("a1") = (unsigned long) (BEG);     \
-  register unsigned long _end __asm ("a2") = (unsigned long) (END);     \
-  register unsigned long _flg __asm ("a3") = 0;                         \
-  __asm __volatile ("swi 0x9f0002               @ sys_cacheflush"       \
-                    : "=r" (_beg)                                       \
-                    : "0" (_beg), "r" (_end), "r" (_flg));              \
-}
-/*
- *  Cache flush code grabbed from a Dec 1999 posting on libc-hacker 
- *  mailing list
- */
-extern void __clear_cache(char*, char *);
+#ifndef CLEAR_CACHE_DEFINED
+extern void __clear_cache(void *, void *);
+#endif
 
 static void
 arm8_flush(void *base, void *limit)
diff -ur spack-src.org/config.h.cmake spack-src/config.h.cmake
--- spack-src.org/config.h.cmake	2020-03-26 16:38:53.358339744 +0900
+++ spack-src/config.h.cmake	2020-03-26 16:52:52.256419382 +0900
@@ -13,10 +13,13 @@
 #cmakedefine HAVE_DIS_ASM_H
 
 /* Define to 1 if you have the <dlfcn.h> header file. */
-#undef HAVE_DLFCN_H
+#cmakedefine HAVE_DLFCN_H
 
 /* Define to 1 if you have the <inttypes.h> header file. */
-#undef HAVE_INTTYPES_H
+#cmakedefine HAVE_INTTYPES_H
+
+/* Define to 1 if you have __clear_cache is defined  */
+#cmakedefine CLEAR_CACHE_DEFINED
 
 /* Define to 1 if you have the <malloc.h> header file. */
 #cmakedefine HAVE_MALLOC_H