diff --git a/database.cc b/database.cc
index 3f8ea903..3f020227 100644
--- a/database.cc
+++ b/database.cc
@@ -124,8 +124,7 @@ _find_prefix (const char *name)
 	if (strcmp (name, BOOLEAN_PREFIX_EXTERNAL[i].name) == 0)
 	    return BOOLEAN_PREFIX_EXTERNAL[i].prefix;
 
-    fprintf (stderr, "Internal error: No prefix exists for '%s'\n", name);
-    exit (1);
+    INTERNAL_ERROR ("No prefix exists for '%s'\n", name);
 
     return "";
 }
diff --git a/message-file.c b/message-file.c
index fd7e68b4..cb2bf665 100644
--- a/message-file.c
+++ b/message-file.c
@@ -125,10 +125,8 @@ notmuch_message_file_restrict_headersv (notmuch_message_file_t *message,
 {
     char *header;
 
-    if (message->parsing_started ) {
-	fprintf (stderr, "Error: notmuch_message_file_restrict_headers called after parsing has started\n");
-	exit (1);
-    }
+    if (message->parsing_started)
+	INTERNAL_ERROR ("notmuch_message_file_restrict_headers called after parsing has started");
 
     while (1) {
 	header = va_arg (va_headers, char*);
@@ -305,11 +303,9 @@ notmuch_message_file_get_header (notmuch_message_file_t *message,
 	! g_hash_table_lookup_extended (message->headers,
 					header_desired, NULL, NULL))
     {
-	fprintf (stderr,
-		 "Internal error: Attempt to get header \"%s\" which was not\n"
-		 "included in call to notmuch_message_file_restrict_headers\n",
-		 header_desired);
-	exit (1);
+	INTERNAL_ERROR ("Attempt to get header \"%s\" which was not\n"
+			"included in call to notmuch_message_file_restrict_headers\n",
+			header_desired);
     }
 
     return NULL;
diff --git a/message.cc b/message.cc
index b66ca7e2..7a6c01d2 100644
--- a/message.cc
+++ b/message.cc
@@ -197,8 +197,7 @@ _notmuch_message_create_for_message_id (const void *talloc_owner,
 
     if (private_status >= (notmuch_private_status_t) NOTMUCH_STATUS_LAST_STATUS)
     {
-	fprintf (stderr, "Internal error: Failed to find document immediately after adding it.\n");
-	exit (1);
+	INTERNAL_ERROR ("Failed to find document immediately after adding it.\n");
     }
 
     *status = (notmuch_status_t) private_status;
@@ -218,9 +217,8 @@ notmuch_message_get_message_id (notmuch_message_t *message)
     i.skip_to (_find_prefix ("id"));
 
     if (i == message->doc.termlist_end ()) {
-	fprintf (stderr, "Internal error: Message with document ID of %d has no message ID.\n",
-		 message->doc_id);
-	exit (1);
+	INTERNAL_ERROR ("Message with document ID of %d has no message ID.\n",
+			message->doc_id);
     }
 
     message->message_id = talloc_strdup (message, (*i).c_str () + 1);
@@ -468,9 +466,8 @@ notmuch_message_add_tag (notmuch_message_t *message, const char *tag)
 
     status = _notmuch_message_add_term (message, "tag", tag);
     if (status) {
-	fprintf (stderr, "Internal error: _notmuch_message_add_term return unexpected value: %d\n",
-		 status);
-	exit (1);
+	INTERNAL_ERROR ("_notmuch_message_add_term return unexpected value: %d\n",
+			status);
     }
 
     _notmuch_message_sync (message);
@@ -491,9 +488,8 @@ notmuch_message_remove_tag (notmuch_message_t *message, const char *tag)
 
     status = _notmuch_message_remove_term (message, "tag", tag);
     if (status) {
-	fprintf (stderr, "Internal error: _notmuch_message_remove_term return unexpected value: %d\n",
-		 status);
-	exit (1);
+	INTERNAL_ERROR ("_notmuch_message_remove_term return unexpected value: %d\n",
+			status);
     }
 
     _notmuch_message_sync (message);
diff --git a/notmuch-private.h b/notmuch-private.h
index 53ea75fa..53b4f1dd 100644
--- a/notmuch-private.h
+++ b/notmuch-private.h
@@ -48,6 +48,20 @@ NOTMUCH_BEGIN_DECLS
 
 #define COMPILE_TIME_ASSERT(pred) ((void)sizeof(char[1 - 2*!(pred)]))
 
+/* There's no point in continuing when we've detected that we've done
+ * something wrong internally (as opposed to the user passing in a
+ * bogus value).
+ *
+ * Note that __location__ comes from talloc.h.
+ */
+#define INTERNAL_ERROR(format, ...)			\
+    do {						\
+	fprintf(stderr,					\
+		"Internal error: " format " (%s)\n",	\
+		##__VA_ARGS__, __location__);		\
+	exit (1);					\
+    } while (0)
+
 /* Thanks to Andrew Tridgell's (SAMBA's) talloc for this definition of
  * unlikely. The talloc source code comes to us via the GNU LGPL v. 3.
  */
diff --git a/notmuch.c b/notmuch.c
index 46c3c63b..c5fef0e8 100644
--- a/notmuch.c
+++ b/notmuch.c
@@ -43,6 +43,20 @@
 
 #include <glib.h> /* g_strdup_printf */
 
+/* There's no point in continuing when we've detected that we've done
+ * something wrong internally (as opposed to the user passing in a
+ * bogus value).
+ *
+ * Note that __location__ comes from talloc.h.
+ */
+#define INTERNAL_ERROR(format, ...)			\
+    do {						\
+	fprintf(stderr,					\
+		"Internal error: " format " (%s)\n",	\
+		##__VA_ARGS__, __location__);		\
+	exit (1);					\
+    } while (0)
+
 #define ARRAY_SIZE(arr) (sizeof (arr) / sizeof (arr[0]))
 
 typedef int (*command_function_t) (int argc, char *argv[]);
@@ -255,8 +269,7 @@ add_files_recursive (notmuch_database_t *notmuch,
 			ret = status;
 			goto DONE;
 		    default:
-			fprintf (stderr, "Internal error: add_message returned unexpected value: %d\n",  status);
-			ret = status;
+			INTERNAL_ERROR ("add_message returned unexpected value: %d",  status);
 			goto DONE;
 		}
 		if (state->processed_files % 1000 == 0)
diff --git a/query.cc b/query.cc
index f5ee7aad..88d76ef1 100644
--- a/query.cc
+++ b/query.cc
@@ -178,8 +178,7 @@ notmuch_results_get (notmuch_results_t *results)
     if (message == NULL &&
 	status == NOTMUCH_PRIVATE_STATUS_NO_DOCUMENT_FOUND)
     {
-	fprintf (stderr, "Internal error: a results iterator contains a non-existent document ID.\n");
-	exit (1);
+	INTERNAL_ERROR ("a results iterator contains a non-existent document ID.\n");
     }
 
     return message;
diff --git a/xutil.c b/xutil.c
index eadd3783..26761d78 100644
--- a/xutil.c
+++ b/xutil.c
@@ -104,10 +104,8 @@ xregcomp (regex_t *preg, const char *regex, int cflags)
 	char *error = xmalloc (error_size);
 
 	regerror (rerr, preg, error, error_size);
-	fprintf (stderr, "Internal error compiling regex %s: %s\n",
-		 regex, error);
-	free (error);
-	exit (1);
+	INTERNAL_ERROR ("compiling regex %s: %s\n",
+			regex, error);
     }
 }
 
@@ -122,11 +120,9 @@ xregexec (const regex_t *preg, const char *string,
 	return rerr;
 
     for (i = 0; i < nmatch; i++) {
-	if (pmatch[i].rm_so == -1) {
-	    fprintf (stderr, "Internal error matching regex against %s: Sub-match %d not found\n",
-		     string, i);
-	    exit (1);
-	}
+	if (pmatch[i].rm_so == -1)
+	    INTERNAL_ERROR ("matching regex against %s: Sub-match %d not found\n",
+			    string, i);
     }
 
     return 0;