diff --git a/potx.inc b/potx.inc
index 14d4824..3170c2c 100644
--- a/potx.inc
+++ b/potx.inc
@@ -984,6 +984,11 @@ function _potx_find_log_calls($file, $save_callback) {
             $depth--;
           }
           $tn++;
+          if ($depth < 0) {
+            // There is no second argument. This log() call was a false
+            // positive, continue with the next one.
+            continue 2;
+          }
         }
         // Get further parameters
         list($comma, $message, $par2) = array($_potx_tokens[$tn], $_potx_tokens[$tn+1], $_potx_tokens[$tn+2]);
@@ -1039,6 +1044,11 @@ function _potx_find_format_plural_calls($file, $save_callback, $function_name =
             $depth--;
           }
           $tn++;
+          if ($depth < 0) {
+            // There is no second argument. This $function_name() call was a
+            // false positive, continue with the next one.
+            continue 2;
+          }
         }
         // Get further parameters
         list($comma1, $singular, $comma2, $plural, $par2) = array($_potx_tokens[$tn], $_potx_tokens[$tn+1], $_potx_tokens[$tn+2], $_potx_tokens[$tn+3], $_potx_tokens[$tn+4]);
diff --git a/tests/potx_test_6.module b/tests/potx_test_6.module
index ca7178b..198c63e 100644
--- a/tests/potx_test_6.module
+++ b/tests/potx_test_6.module
@@ -39,6 +39,8 @@ function potx_test_6_menu_alter(&$items) {
 function potx_test_6_page() {
   t('This is a test string.');
   format_plural($count, '1 test string', '@count test strings');
+  format_plural($count);
+  format_plural();
   watchdog('test watchdog type', 'My watchdog message');
 
   st('Installer only test string');
diff --git a/tests/potx_test_8.module b/tests/potx_test_8.module
index def9a05..a9b70fc 100644
--- a/tests/potx_test_8.module
+++ b/tests/potx_test_8.module
@@ -25,8 +25,11 @@ function potx_test_8_example() {
   $g->alert('Alert message');
   $h->emergency('Emergency message');
   $i->log(1, 'Log message');
-  $i->log($boo, 'Log message 2');
-  $i->log(potx_test_8_sample(), 'Log message 3');
+  $j->log('false positive');
+  $k->log($boo, 'Log message 2');
+  $l->log($another_false_positive);
+  $m->log(potx_test_8_sample(), 'Log message 3');
+  $n->log();
 }
 
 /**
@@ -64,6 +67,8 @@ class PotxTestD8 {
   function testFormatPlural() {
     $this->formatPlural($count, '1 formatPlural test string', '@count formatPlural test strings');
     $this->formatPlural($count, '1 formatPlural test string in context', '@count formatPlural test strings in context', array(), array('context' => 'Test context'));
+    $this->formatPlural($count);
+    $this->formatPlural();
 
     \Drupal::translation()->formatPlural($count, '1 translation->formatPlural test string in context', '@count translation->formatPlural test strings in context', array(), array('context' => 'Test context'));
     \Drupal::translation()->formatPlural($count, '1 translation->formatPlural test string', '@count translation->formatPlural test strings');