diff --git a/src/cc65/codeopt.c b/src/cc65/codeopt.c
index e9cf8914f..f7e3d4a1a 100644
--- a/src/cc65/codeopt.c
+++ b/src/cc65/codeopt.c
@@ -129,11 +129,11 @@ static OptFunc DOptBoolUnary3   = { OptBoolUnary3,   "OptBoolUnary3",    40, 0,
 static OptFunc DOptBranchDist   = { OptBranchDist,   "OptBranchDist",     0, 0, 0, 0, 0, 0 };
 static OptFunc DOptBranchDist2  = { OptBranchDist2,  "OptBranchDist2",    0, 0, 0, 0, 0, 0 };
 static OptFunc DOptCmp1         = { OptCmp1,         "OptCmp1",          42, 0, 0, 0, 0, 0 };
-static OptFunc DOptCmp10        = { OptCmp10,        "OptCmp10",         33, 0, 0, 0, 0, 0 };
 static OptFunc DOptCmp2         = { OptCmp2,         "OptCmp2",          85, 0, 0, 0, 0, 0 };
 static OptFunc DOptCmp3         = { OptCmp3,         "OptCmp3",          75, 0, 0, 0, 0, 0 };
 static OptFunc DOptCmp4         = { OptCmp4,         "OptCmp4",          75, 0, 0, 0, 0, 0 };
 static OptFunc DOptCmp5         = { OptCmp5,         "OptCmp5",         100, 0, 0, 0, 0, 0 };
+static OptFunc DOptCmp6         = { OptCmp6,         "OptCmp6",          33, 0, 0, 0, 0, 0 };
 static OptFunc DOptCmp7         = { OptCmp7,         "OptCmp7",          85, 0, 0, 0, 0, 0 };
 static OptFunc DOptCmp8         = { OptCmp8,         "OptCmp8",          50, 0, 0, 0, 0, 0 };
 static OptFunc DOptCmp9         = { OptCmp9,         "OptCmp9",          85, 0, 0, 0, 0, 0 };
@@ -252,11 +252,11 @@ static OptFunc* OptFuncs[] = {
     &DOptBranchDist,
     &DOptBranchDist2,
     &DOptCmp1,
-    &DOptCmp10,
     &DOptCmp2,
     &DOptCmp3,
     &DOptCmp4,
     &DOptCmp5,
+    &DOptCmp6,
     &DOptCmp7,
     &DOptCmp8,
     &DOptCmp9,
@@ -731,7 +731,7 @@ static unsigned RunOptGroup3 (CodeSeg* S)
         C += RunOptFunc (S, &DOptCondBranch3, 1);
         C += RunOptFunc (S, &DOptCondBranchC, 1);
         C += RunOptFunc (S, &DOptRTSJumps1, 1);
-        C += RunOptFunc (S, &DOptCmp10, 1);         /* After OptRTSJumps1 */
+        C += RunOptFunc (S, &DOptCmp6, 1);          /* After OptRTSJumps1 */
         C += RunOptFunc (S, &DOptBoolCmp, 1);
         C += RunOptFunc (S, &DOptBoolTrans, 1);
         C += RunOptFunc (S, &DOptBNegA2, 1);        /* After OptCondBranch's */
diff --git a/src/cc65/coptcmp.c b/src/cc65/coptcmp.c
index 25499dc3c..8f487969e 100644
--- a/src/cc65/coptcmp.c
+++ b/src/cc65/coptcmp.c
@@ -503,6 +503,51 @@ unsigned OptCmp5 (CodeSeg* S)
 
 
 
+unsigned OptCmp6 (CodeSeg* S)
+/* Remove compare instructions before an RTS or an subroutine call that doesn't
+** use the flags.
+*/
+{
+    unsigned Changes = 0;
+    unsigned I;
+
+    /* Walk over the entries */
+    I = 0;
+    while (I < CS_GetEntryCount (S)) {
+
+        CodeEntry* N;
+
+        /* Get next entry */
+        CodeEntry* E = CS_GetEntry (S, I);
+
+        /* Check for a compare followed by something else.
+        ** Note: The test could be improved by checking the flag usage of the
+        ** function explicitly against the flags set by the compare instruction.
+        ** For current code generation this makes no difference, however.
+        */
+        if ((E->Info & OF_CMP) != 0                     &&
+            (N = CS_GetNextEntry (S, I)) != 0           &&
+            (N->OPC == OP65_RTS                 ||  /* Either RTS, or ... */
+             (N->OPC == OP65_JSR            &&      /* ... or JSR ... */
+              N->JumpTo == 0                &&      /* ... to external ... */
+              (N->Use & PSTATE_ALL) == 0    &&      /* ... with no flags used ... */
+              (N->Chg & PSTATE_ALL) == PSTATE_ALL))) {  /* ... but all destroyed */
+
+            /* Found, remove the compare */
+            CS_DelEntry (S, I);
+            ++Changes;
+        }
+
+        /* Next entry */
+        ++I;
+    }
+
+    /* Return the number of changes made */
+    return Changes;
+}
+
+
+
 unsigned OptCmp7 (CodeSeg* S)
 /* Search for a sequence ldx/txa/branch and remove the txa if A is not
 ** used later.
@@ -741,40 +786,3 @@ unsigned OptCmp9 (CodeSeg* S)
     /* Return the number of changes made */
     return Changes;
 }
-
-
-
-unsigned OptCmp10 (CodeSeg* S)
-/* Remove compare instructions before an RTS. This is safe since no C function
-** passes back something in the flags.
-*/
-{
-    unsigned Changes = 0;
-    unsigned I;
-
-    /* Walk over the entries */
-    I = 0;
-    while (I < CS_GetEntryCount (S)) {
-
-        CodeEntry* N;
-
-        /* Get next entry */
-        CodeEntry* E = CS_GetEntry (S, I);
-
-        /* Check for a compare followed by an RTS */
-        if ((E->Info & OF_CMP) != 0             &&      /* Compare insn */
-            (N = CS_GetNextEntry (S, I)) != 0   &&      /* Next entry ... */
-            N->OPC == OP65_RTS) {                       /* ... is RTS */
-
-            /* Found, remove the compare */
-            CS_DelEntry (S, I);
-            ++Changes;
-        }
-
-        /* Next entry */
-        ++I;
-    }
-
-    /* Return the number of changes made */
-    return Changes;
-}
diff --git a/src/cc65/coptcmp.h b/src/cc65/coptcmp.h
index ff58d37df..acd146822 100644
--- a/src/cc65/coptcmp.h
+++ b/src/cc65/coptcmp.h
@@ -123,6 +123,11 @@ unsigned OptCmp5 (CodeSeg* S);
 **      jne/jeq L2
 */
 
+unsigned OptCmp6 (CodeSeg* S);
+/* Remove compare instructions before an RTS or an exit by jumping to some
+** other function.
+*/
+
 unsigned OptCmp7 (CodeSeg* S);
 /* Search for a sequence ldx/txa/branch and remove the txa if A is not
 ** used later.
@@ -146,11 +151,6 @@ unsigned OptCmp9 (CodeSeg* S);
 ** flag instead of the carry flag and remove the asl.
 */
 
-unsigned OptCmp10 (CodeSeg* S);
-/* Remove compare instructions before an RTS. This is safe since no C function
-** passes back something in the flags.
-*/
-
 
 
 /* End of coptcmp.h */