Index: src/macros.h
==================================================================
--- src/macros.h
+++ src/macros.h
@@ -148,10 +148,13 @@
 # define OF_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
 #else
 # define OF_GCC_VERSION 0
 #endif
 
+#define OF_STRINGIFY(s) OF_STRINGIFY2(s)
+#define OF_STRINGIFY2(s) #s
+
 #ifndef __has_feature
 # define __has_feature(x) 0
 #endif
 
 #ifndef __has_attribute
@@ -356,14 +359,16 @@
 
 #define OF_RETAIN_COUNT_MAX UINT_MAX
 #define OF_NOT_FOUND SIZE_MAX
 
 #ifdef OBJC_COMPILING_RUNTIME
-# define OF_ENSURE(cond)						   \
-	do {								   \
-		if OF_UNLIKELY (!(cond))				   \
-			OBJC_ERROR("Failed to ensure condition:\n" #cond); \
+# define OF_ENSURE(cond)						\
+	do {								\
+		if OF_UNLIKELY (!(cond))				\
+			objc_error("ObjFWRT @ " __FILE__ ":"		\
+			    OF_STRINGIFY(__LINE__),			\
+			    "Failed to ensure condition:\n" #cond);	\
 	} while(0)
 #else
 # define OF_ENSURE(cond)						\
 	do {								\
 		if OF_UNLIKELY (!(cond)) {				\

Index: src/runtime/misc.m
==================================================================
--- src/runtime/misc.m
+++ src/runtime/misc.m
@@ -51,28 +51,23 @@
 {
 	enumerationMutationHandler = handler;
 }
 
 void
-objc_error(const char *file, unsigned int line, const char *format, ...)
+objc_error(const char *title, const char *format, ...)
 {
 #ifdef OF_AMIGAOS
-# define BUF_LEN 256
-	char title[BUF_LEN];
+# define BUF_LEN 512
 	char message[BUF_LEN];
 	int status;
 	va_list args;
 	struct Library *IntuitionBase;
 # ifdef OF_AMIGAOS4
 	struct IntuitionIFace *IIntuition;
 # endif
 	struct EasyStruct easy;
 
-	status = snprintf(title, BUF_LEN, "ObjFWRT @ %s:%u", file, line);
-	if (status <= 0 || status >= BUF_LEN)
-		title[0] = '\0';
-
 	va_start(args, format);
 	status = vsnprintf(message, BUF_LEN, format, args);
 	if (status <= 0 || status >= BUF_LEN)
 		message[0] = '\0';
 	va_end(args);
@@ -109,11 +104,11 @@
 #else
 	va_list args;
 
 	va_start(args, format);
 
-	fprintf(stderr, "[ObjFWRT @ %s:%u] ", file, line);
+	fprintf(stderr, "[%s] ", title);
 	vfprintf(stderr, format, args);
 	fprintf(stderr, "\n");
 	fflush(stderr);
 
 	va_end(args);

Index: src/runtime/private.h
==================================================================
--- src/runtime/private.h
+++ src/runtime/private.h
@@ -341,13 +341,15 @@
 
 	return dtable->buckets[i]->buckets[j];
 #endif
 }
 
-extern void OF_NO_RETURN_FUNC objc_error(const char *_Nonnull file,
-    unsigned int line, const char *_Nonnull format, ...);
-#define OBJC_ERROR(...) objc_error(__FILE__, __LINE__, __VA_ARGS__)
+extern void OF_NO_RETURN_FUNC objc_error(const char *_Nonnull title,
+    const char *_Nonnull format, ...);
+#define OBJC_ERROR(...)							\
+	objc_error("ObjFWRT @ " __FILE__ ":" OF_STRINGIFY(__LINE__),	\
+	    __VA_ARGS__)
 
 #if defined(OF_ELF)
 # if defined(OF_X86_64) || defined(OF_X86) || defined(OF_POWERPC) || \
     defined(OF_ARM64) || defined(OF_ARM) || \
     defined(OF_MIPS64_N64) || defined(OF_MIPS) || \