diff --git a/xen/arch/x86/hvm/hvm.c b/xen/arch/x86/hvm/hvm.c
index 57363c2ae1..24ccf60d77 100644
--- a/xen/arch/x86/hvm/hvm.c
+++ b/xen/arch/x86/hvm/hvm.c
@@ -3853,7 +3853,7 @@ void hvm_ud_intercept(struct cpu_user_regs *regs)
                                         cs, &addr) &&
              (hvm_copy_from_guest_linear(sig, addr, sizeof(sig),
                                          walk, NULL) == HVMTRANS_okay) &&
-             (memcmp(sig, "\xf\xbxen", sizeof(sig)) == 0) )
+             (memcmp(sig, "\xf\xb" "xen", sizeof(sig)) == 0) )
         {
             regs->rip += sizeof(sig);
             regs->eflags &= ~X86_EFLAGS_RF;
diff --git a/xen/common/decompress.c b/xen/common/decompress.c
index 989336983f..2c2c2ad877 100644
--- a/xen/common/decompress.c
+++ b/xen/common/decompress.c
@@ -19,13 +19,13 @@ int __init decompress(void *inbuf, unsigned int len, void *outbuf)
     if ( len >= 3 && !memcmp(inbuf, "\x42\x5a\x68", 3) )
         return bunzip2(inbuf, len, NULL, NULL, outbuf, NULL, error);
 
-    if ( len >= 6 && !memcmp(inbuf, "\3757zXZ", 6) )
+    if ( len >= 6 && !memcmp(inbuf, "\375" "7zXZ", 6) )
         return unxz(inbuf, len, NULL, NULL, outbuf, NULL, error);
 
     if ( len >= 2 && !memcmp(inbuf, "\135\000", 2) )
         return unlzma(inbuf, len, NULL, NULL, outbuf, NULL, error);
 
-    if ( len >= 5 && !memcmp(inbuf, "\x89LZO", 5) )
+    if ( len >= 5 && !memcmp(inbuf, "\x89" "LZO", 5) )
         return unlzo(inbuf, len, NULL, NULL, outbuf, NULL, error);
 
     if ( len >= 2 && !memcmp(inbuf, "\x02\x21", 2) )
diff --git a/xen/common/xz/stream.h b/xen/common/xz/stream.h
index d36d0fec64..8d9fbbe1b5 100644
--- a/xen/common/xz/stream.h
+++ b/xen/common/xz/stream.h
@@ -18,7 +18,7 @@
 
 #define STREAM_HEADER_SIZE 12
 
-#define HEADER_MAGIC "\3757zXZ"
+#define HEADER_MAGIC "\375" "7zXZ"
 #define HEADER_MAGIC_SIZE 6
 
 #define FOOTER_MAGIC "YZ"