diff --git a/engine/common/bothdefs.h b/engine/common/bothdefs.h
index 7f73cbd83..6b14929b1 100644
--- a/engine/common/bothdefs.h
+++ b/engine/common/bothdefs.h
@@ -917,22 +917,29 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 	#define FTE_ALIGN(a)
 #endif
 
+//fte_inline must only be used in headers, and requires one and ONLY one fte_inlinebody elsewhere.
+//fte_inlinebody must be used on a prototype OUTSIDE of a header.
+//fte_inlinestatic must not be used inside any headers at all.
 #if __STDC_VERSION__ >= 199901L
 	//C99 specifies that an inline function is used as a hint. there should be an actual body/copy somewhere (extern inline foo).
 	#define fte_inline inline	//must have non-line 'int foo();' somewhere
 	#define fte_inlinebody extern inline
+	#define fte_inlinestatic static inline
 #elif defined(_MSC_VER)
 	//msvc will inline like C++. and that's fine.
 	#define fte_inline __inline //c++ style
 	#define fte_inlinebody
+	#define fte_inlinestatic static __inline
 #elif (__GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 5))
 	//gcc will generally inline where it can - so long as its static. but that doesn't stop it warning
 	#define fte_inline __attribute__((unused)) static
 	#define fte_inlinebody static
+	#define fte_inlinestatic static
 #else
 	//make it static so we at least don't get errors (might still get warnings. see above)
 	#define fte_inline static
 	#define fte_inlinebody static
+	#define fte_inlinestatic static
 #endif
 
 
diff --git a/engine/common/cmd.c b/engine/common/cmd.c
index f6fb7deb0..653c3b22d 100644
--- a/engine/common/cmd.c
+++ b/engine/common/cmd.c
@@ -2195,7 +2195,7 @@ struct cmdargcompletion_ctx_s
 	cmd_completion_t *res;
 	const char *desc;
 };
-static fte_inline int Q_tolower(char c)
+fte_inlinestatic int Q_tolower(char c)
 {
 	if (c >= 'a' && c <= 'z')
 		c -= ('a' - 'A');
diff --git a/engine/common/common.c b/engine/common/common.c
index 566a7ee76..998db3887 100644
--- a/engine/common/common.c
+++ b/engine/common/common.c
@@ -480,7 +480,7 @@ char *Q_strlwr(char *s)
 	return ret;
 }
 
-static char fte_inline Q_tolower(char c)
+fte_inlinestatic char Q_tolower(char c)
 {
 	if (c >= 'A' && c <= 'Z')
 		return c-'A'+'a';