diff --git a/config.d/typedefs_structs_compiler.m4 b/config.d/typedefs_structs_compiler.m4
index 3ba73b7d6..8e6acac2e 100644
--- a/config.d/typedefs_structs_compiler.m4
+++ b/config.d/typedefs_structs_compiler.m4
@@ -74,9 +74,9 @@ AH_VERBATIM([HAVE___ATTRIBUTE__GCC_STRUCT],
 #endif])
 
 AC_MSG_CHECKING(for __builtin_expect)
-AC_TRY_COMPILE(
-	[long (*foo) (long, long) = __builtin_expect;],
-	[],
+AC_TRY_LINK(
+	[int x;],
+	[if (__builtin_expect(!x, 1)) {}],
 	AC_DEFINE(HAVE___BUILTIN_EXPECT)
 	AC_MSG_RESULT(yes),
 	AC_MSG_RESULT(no)
diff --git a/include/QF/pr_comp.h b/include/QF/pr_comp.h
index 4cc274f98..7bac7eb01 100644
--- a/include/QF/pr_comp.h
+++ b/include/QF/pr_comp.h
@@ -346,8 +346,8 @@ typedef union pr_type_u {
 	string_t    string_var;
 	func_t      func_var;
 	pr_int_t    entity_var;
-	float       vector_var[1];	// really 3, but this structure must be 32 bits
-	float       quat_var[1];	// really 4, but this structure must be 32 bits
+	float       vector_var[0];	// really 3, but this structure must be 32 bits
+	float       quat_var[0];	// really 4, but this structure must be 32 bits
 	pr_int_t    integer_var;
 	pointer_t   pointer_var;
 	pr_uint_t   uinteger_var;
diff --git a/include/QF/progs.h b/include/QF/progs.h
index 7c8bb3341..1c706ae4c 100644
--- a/include/QF/progs.h
+++ b/include/QF/progs.h
@@ -221,7 +221,7 @@ struct edict_s {
 	int         entnum;			///< number of this entity
 	float       freetime;		///< sv.time when the object was freed
 	void       *edata;			///< external per-edict data
-	pr_type_t   v[1];			///< fields from progs
+	pr_type_t   v[];			///< fields from progs
 };
 
 // pr_edict.c
diff --git a/libs/gamecode/pr_load.c b/libs/gamecode/pr_load.c
index b9a6df13a..82864b096 100644
--- a/libs/gamecode/pr_load.c
+++ b/libs/gamecode/pr_load.c
@@ -177,7 +177,7 @@ PR_LoadProgsFile (progs_t *pr, QFile *file, int size, int max_edicts, int zone)
 	// size of edict asked for by progs
 	pr->pr_edict_size = max (1, progs.entityfields) * 4;
 	// size of engine data
-	pr->pr_edict_size += sizeof (edict_t) - sizeof (pr_type_t);
+	pr->pr_edict_size += sizeof (edict_t);
 	// round off to next highest whole word address (esp for Alpha)
 	// this ensures that pointers in the engine data area are always
 	// properly aligned
diff --git a/libs/util/plugin.c b/libs/util/plugin.c
index 31fa725fd..7baa8df72 100644
--- a/libs/util/plugin.c
+++ b/libs/util/plugin.c
@@ -98,11 +98,13 @@ loaded_plugin_delete (void *lp, void *unused)
 static int
 pi_close_lib (void *handle)
 {
+	if (handle) {
 #if defined(HAVE_DLOPEN)
-	return (dlclose (handle) == 0);
+		return (dlclose (handle) == 0);
 #elif defined (_WIN32)
-	return (FreeLibrary (handle) == 0);
+		return (FreeLibrary (handle) == 0);
 #endif
+	}
 	return 1;
 }
 
diff --git a/nq/source/sv_main.c b/nq/source/sv_main.c
index 25def54ac..b666516f6 100644
--- a/nq/source/sv_main.c
+++ b/nq/source/sv_main.c
@@ -45,7 +45,7 @@ server_t    sv;
 server_static_t svs;
 double      sv_frametime;
 
-char        localmodels[MAX_MODELS][5];	// inline model names for precache
+char        localmodels[MAX_MODELS][6];	// inline model names for precache
 
 int sv_protocol = PROTOCOL_FITZQUAKE;
 
diff --git a/qw/source/cl_slist.c b/qw/source/cl_slist.c
index 569b711ce..585e6aa47 100644
--- a/qw/source/cl_slist.c
+++ b/qw/source/cl_slist.c
@@ -348,7 +348,7 @@ gettoklen (char *str, int req, char delim)
 	int         len = 0;
 
 	start = gettokstart (str, req, delim);
-	if (start == '\0') {
+	if (*start == '\0') {
 		return 0;
 	}
 	while (*start != delim && *start != '\0') {
diff --git a/tools/qfcc/source/qp-lex.l b/tools/qfcc/source/qp-lex.l
index e98b6511b..0bca559c9 100644
--- a/tools/qfcc/source/qp-lex.l
+++ b/tools/qfcc/source/qp-lex.l
@@ -296,7 +296,9 @@ convert_relop (const char *relop)
 #ifdef YY_FLEX_REALLOC_HACK
 static __attribute__ ((used)) void *(*const yy_flex_realloc_hack)(void *,yy_size_t) = yy_flex_realloc;
 #else
+#ifdef yyunput
 static __attribute__ ((used)) void (*yyunput_hack)(int, char*) = yyunput;
+#endif
 static __attribute__ ((used)) int (*input_hack)(void) = input;
 #endif