diff --git a/src/cl65/main.c b/src/cl65/main.c
index 900602c87..8d8aac932 100644
--- a/src/cl65/main.c
+++ b/src/cl65/main.c
@@ -673,7 +673,7 @@ static void Compile (const char* File)
 
     if (DoAssemble) {
         /* set a temporary output file name */
-        TmpFile = MakeTmpFilename(File, ".s");
+        TmpFile = MakeTmpFilename(".s");
         CmdSetOutput (&CC65, TmpFile);
     }
 
diff --git a/src/common/fname.c b/src/common/fname.c
index c5000bc72..f026f776d 100644
--- a/src/common/fname.c
+++ b/src/common/fname.c
@@ -119,16 +119,26 @@ char* MakeFilename (const char* Origin, const char* Ext)
 
 
 
-char* MakeTmpFilename (const char* Origin, const char* Ext)
+char* MakeTmpFilename (const char* Ext)
 /* Make a new temporary file name from Ext.  tmpnam(3) is called
-** and Ext is appended to generate the filename. Origin is ignored.
+** and Ext is appended to generate the filename.
 ** The result is placed in a malloc'ed buffer and returned.
 */
 {
     char* Out;
     char Buffer[L_tmpnam * 2]; /* a lazy way to ensure we have space for Ext */
 
-    tmpnam(Buffer);
+    /*
+    ** gcc emits the following warning here:
+    **
+    ** warning: the use of `tmpnam' is dangerous, better use `mkstemp'
+    **
+    ** however, mkstemp actually opens a file, which we do not want.
+    ** we could write our own version, but then we would have to struggle
+    ** with supporting multiple build environments.  tmpnam(3) is fine
+    ** here.
+    */
+    (void) tmpnam(Buffer);
     strcat(Buffer, Ext);
 
     Out = xmalloc (strlen (Buffer) + 1);
diff --git a/src/common/fname.h b/src/common/fname.h
index 1dc985f93..cd163e4e7 100644
--- a/src/common/fname.h
+++ b/src/common/fname.h
@@ -59,7 +59,7 @@ char* MakeFilename (const char* Origin, const char* Ext);
 ** The function may be used to create "foo.o" from "foo.s".
 */
 
-char* MakeTmpFilename (const char* Origin, const char* Ext);
+char* MakeTmpFilename (const char* Ext);
 /* Make a new temporary file name from Ext.  tmpnam(3) is called
 ** and Ext is appended to generate the filename. Origin is ignored.
 ** The result is placed in a malloc'ed buffer and returned.