diff --git a/src/libCom/osi/compiler/borland/compilerSpecific.h b/src/libCom/osi/compiler/borland/compilerSpecific.h
index 9a86e1aae..9251bfe29 100644
--- a/src/libCom/osi/compiler/borland/compilerSpecific.h
+++ b/src/libCom/osi/compiler/borland/compilerSpecific.h
@@ -1,4 +1,3 @@
-
 /*************************************************************************\
 * Copyright (c) 2008 UChicago Argonne LLC, as Operator of Argonne
 *     National Laboratory.
@@ -42,14 +41,5 @@
 
 #endif /* __cplusplus */
 
-/*
- * Enable format-string checking if possible
- */
-#define EPICS_PRINTF_STYLE(f,a)
-
-/*
- * Deprecation marker
- */
-#define EPICS_DEPRECATED
 
 #endif  /* ifndef compilerSpecific_h */
diff --git a/src/libCom/osi/compiler/clang/compilerSpecific.h b/src/libCom/osi/compiler/clang/compilerSpecific.h
index 881c30f42..9c6b237c5 100644
--- a/src/libCom/osi/compiler/clang/compilerSpecific.h
+++ b/src/libCom/osi/compiler/clang/compilerSpecific.h
@@ -1,4 +1,3 @@
-
 /*************************************************************************\
 * Copyright (c) 2008 UChicago Argonne LLC, as Operator of Argonne
 *     National Laboratory.
@@ -21,12 +20,6 @@
 #   error compiler/clang/compilerSpecific.h is only for use with the clang compiler
 #endif
 
-/*
- * WARNING: the current state of this file is only based on reading clang manuals
- * and has not actually been tested with the compiler
- */
-#pragma warning compiler/clang/compilerSpecific.h is based on reading the manual, but hasnt been tested with the clang compiler
-
 #ifdef __cplusplus
 
 /*
@@ -39,21 +32,18 @@
 #endif /* __cplusplus */
 
 /*
- * Enable format-string checking if possible
+ * __has_attribute() is not supported on all versions of clang yet
  */
-#if __has_attribute(format)
-#   define EPICS_PRINTF_STYLE(f,a) __attribute__((format(__printf__,f,a)))
-#else
-#   define EPICS_PRINTF_STYLE
-#endif
 
 /*
- * Deprecation marker if possible
+ * Enable format-string checking
  */
-#if __has_attribute(deprecated)
-#   define EPICS_DEPRECATED __attribute__((deprecated))
-#else
-#   define EPICS_DEPRECATED
-#endif
+#define EPICS_PRINTF_STYLE(f,a) __attribute__((format(__printf__,f,a)))
+
+/*
+ * Deprecation marker
+ */
+#define EPICS_DEPRECATED __attribute__((deprecated))
+
 
 #endif  /* ifndef compilerSpecific_h */
diff --git a/src/libCom/osi/compiler/default/compilerSpecific.h b/src/libCom/osi/compiler/default/compilerSpecific.h
index da2a21acc..f2a3f8c36 100644
--- a/src/libCom/osi/compiler/default/compilerSpecific.h
+++ b/src/libCom/osi/compiler/default/compilerSpecific.h
@@ -1,4 +1,3 @@
-
 /*************************************************************************\
 * Copyright (c) 2008 UChicago Argonne LLC, as Operator of Argonne
 *     National Laboratory.
@@ -30,16 +29,5 @@
 
 #endif /* __cplusplus */
 
-/*
- * Enable format-string checking if possible
- * (our default guess is that the compiler doesnt implement non-standard extensions)
- */
-#define EPICS_PRINTF_STYLE(f,a)
-
-/*
- * Deprecation marker
- * (our default guess is that the compiler doesnt implement non-standard extensions)
- */
-#define EPICS_DEPRECATED
 
 #endif  /* ifndef compilerSpecific_h */
diff --git a/src/libCom/osi/compiler/gcc/compilerSpecific.h b/src/libCom/osi/compiler/gcc/compilerSpecific.h
index 3dc505c29..efd17e4b2 100644
--- a/src/libCom/osi/compiler/gcc/compilerSpecific.h
+++ b/src/libCom/osi/compiler/gcc/compilerSpecific.h
@@ -1,4 +1,3 @@
-
 /*************************************************************************\
 * Copyright (c) 2008 UChicago Argonne LLC, as Operator of Argonne
 *     National Laboratory.
@@ -20,6 +19,10 @@
 #ifndef __GNUC__
 #   error compiler/gcc/compilerSpecific.h is only for use with the gnu compiler
 #endif
+
+#ifdef __clang__
+#   error compiler/gcc/compilerSpecific.h is not for use with the clang compiler
+#endif
  
 #ifdef __cplusplus
 
@@ -55,8 +58,7 @@
  */
 #if  (__GNUC__ > 2)
 #   define EPICS_DEPRECATED __attribute__((deprecated))
-#else
-#   define EPICS_DEPRECATED
 #endif
 
+
 #endif  /* ifndef compilerSpecific_h */
diff --git a/src/libCom/osi/compiler/msvc/compilerSpecific.h b/src/libCom/osi/compiler/msvc/compilerSpecific.h
index 64ebf915f..587d534c7 100644
--- a/src/libCom/osi/compiler/msvc/compilerSpecific.h
+++ b/src/libCom/osi/compiler/msvc/compilerSpecific.h
@@ -1,4 +1,3 @@
-
 /*************************************************************************\
 * Copyright (c) 2008 UChicago Argonne LLC, as Operator of Argonne
 *     National Laboratory.
@@ -44,14 +43,5 @@
 
 #endif /* __cplusplus */
 
-/*
- * Enable format-string checking if possible
- */
-#define EPICS_PRINTF_STYLE(f,a)
-
-/*
- * Deprecation marker
- */
-#define EPICS_DEPRECATED
 
 #endif  /* ifndef compilerSpecific_h */
diff --git a/src/libCom/osi/compilerDependencies.h b/src/libCom/osi/compilerDependencies.h
index 7f2acc699..c91133996 100644
--- a/src/libCom/osi/compilerDependencies.h
+++ b/src/libCom/osi/compilerDependencies.h
@@ -1,4 +1,3 @@
-
 /*************************************************************************\
 * Copyright (c) 2008 UChicago Argonne LLC, as Operator of Argonne
 *     National Laboratory.
@@ -44,4 +43,20 @@
 
 #endif /* __cplusplus */
 
+
+#ifndef EPICS_PRINTF_STYLE
+/*
+ * No format-string checking
+ */
+#   define EPICS_PRINTF_STYLE(f,a)
+#endif
+
+#ifndef EPICS_DEPRECATED
+/*
+ * No deprecation markers
+ */
+#define EPICS_DEPRECATED
+#endif
+
+
 #endif  /* ifndef compilerDependencies_h */