diff --git a/src/libCom/freeList/freeListLib.c b/src/libCom/freeList/freeListLib.c
old mode 100644
new mode 100755
index a0ae73837..b8e8e6f23
--- a/src/libCom/freeList/freeListLib.c
+++ b/src/libCom/freeList/freeListLib.c
@@ -107,7 +107,7 @@ epicsShareFunc void * epicsShareAPI freeListMalloc(void *pvt)
             return(0);
         }
         pallocmem->memory = ptemp; /* real allocation */
-        ptemp += REDZONE; /* skip first REDZONE */
+        ptemp = REDZONE + (char *) ptemp; /* skip first REDZONE */
         if(pfl->mallochead)
             pallocmem->next = pfl->mallochead;
         pfl->mallochead = pallocmem;
diff --git a/src/libCom/valgrind/valgrind.h b/src/libCom/valgrind/valgrind.h
old mode 100644
new mode 100755
index 6954d751d..c503172d5
--- a/src/libCom/valgrind/valgrind.h
+++ b/src/libCom/valgrind/valgrind.h
@@ -130,10 +130,10 @@
 #  define PLAT_amd64_darwin 1
 #elif (defined(__MINGW32__) && !defined(__MINGW64__)) \
       || defined(__CYGWIN32__) \
-      || (defined(_WIN32) && defined(_M_IX86))
+      || (defined(_WIN32) && defined(_M_IX86) && defined(__GNUC__))
 #  define PLAT_x86_win32 1
 #elif defined(__MINGW64__) \
-      || (defined(_WIN64) && defined(_M_X64))
+      || (defined(_WIN64) && defined(_M_X64) && defined(__GNUC__))
 #  define PLAT_amd64_win64 1
 #elif defined(__linux__) && defined(__i386__)
 #  define PLAT_x86_linux 1