diff --git a/.github/checks/lastline.sh b/.github/checks/lastline.sh
index d243a01e1..6bb6e0dc5 100755
--- a/.github/checks/lastline.sh
+++ b/.github/checks/lastline.sh
@@ -23,3 +23,4 @@ if [ x"$FILES"x != xx ]; then
     done
     exit -1
 fi
+exit 0
diff --git a/.github/checks/lineendings.sh b/.github/checks/lineendings.sh
index 5b445522f..5baac514e 100755
--- a/.github/checks/lineendings.sh
+++ b/.github/checks/lineendings.sh
@@ -16,3 +16,4 @@ if [ x"$FILES"x != xx ]; then
     done
     exit -1
 fi
+exit 0
diff --git a/.github/checks/noexec.sh b/.github/checks/noexec.sh
index c76ae481d..5e53fe869 100755
--- a/.github/checks/noexec.sh
+++ b/.github/checks/noexec.sh
@@ -16,3 +16,4 @@ if [ x"$FILES"x != xx ]; then
     done
     exit -1
 fi
+exit 0
diff --git a/.github/checks/sorted.sh b/.github/checks/sorted.sh
index 4f53b0484..b5451a21f 100755
--- a/.github/checks/sorted.sh
+++ b/.github/checks/sorted.sh
@@ -36,3 +36,4 @@ function checkarray_quoted_name
 for N in `grep -rl "BEGIN SORTED.SH" "$CHECK_DIR"`; do
     checkarray_quoted_name $N
 done
+exit 0
diff --git a/.github/checks/sorted_codeopt.sh b/.github/checks/sorted_codeopt.sh
index c78662b9d..cfca028dd 100755
--- a/.github/checks/sorted_codeopt.sh
+++ b/.github/checks/sorted_codeopt.sh
@@ -63,6 +63,7 @@ function checkarray
 }
 
 
-for N in `grep -rl "BEGIN DECL SORTED_CODEOPT.SH" "$CHECK_DIR"`; do
-    checkarray $N
+find "$CHECK_DIR" -name \*.\[ch\] -print | while read N; do
+    grep -q "BEGIN DECL SORTED_CODEOPT.SH" "$N" && checkarray $N
 done
+exit 0	   
diff --git a/.github/checks/sorted_opcodes.sh b/.github/checks/sorted_opcodes.sh
index 3e45ea752..34156bde6 100755
--- a/.github/checks/sorted_opcodes.sh
+++ b/.github/checks/sorted_opcodes.sh
@@ -37,4 +37,4 @@ function checkarray_quoted_name
 for N in `grep -rl "BEGIN SORTED_OPCODES.SH" "$CHECK_DIR"`; do
     checkarray_quoted_name $N
 done
-
+exit 0
diff --git a/.github/checks/spaces.sh b/.github/checks/spaces.sh
index e231f6c2d..f2eea6f3f 100755
--- a/.github/checks/spaces.sh
+++ b/.github/checks/spaces.sh
@@ -16,3 +16,4 @@ if [ x"$FILES"x != xx ]; then
     done
     exit -1
 fi
+exit 0
diff --git a/.github/checks/tabs.sh b/.github/checks/tabs.sh
index 80dac3f2d..ed8d45bac 100755
--- a/.github/checks/tabs.sh
+++ b/.github/checks/tabs.sh
@@ -16,3 +16,4 @@ if [ x"$FILES"x != xx ]; then
     done
     exit -1
 fi
+exit 0
diff --git a/libsrc/agat/sysuname.s b/libsrc/agat/sysuname.s
new file mode 100644
index 000000000..b2d2a334f
--- /dev/null
+++ b/libsrc/agat/sysuname.s
@@ -0,0 +1,37 @@
+;
+; Ullrich von Bassewitz, 2003-08-12
+;
+; unsigned char __fastcall__ _sysuname (struct utsname* buf);
+;
+
+        .export         __sysuname, utsdata
+
+        .import         utscopy
+
+        __sysuname = utscopy
+
+;--------------------------------------------------------------------------
+; Data. We define a fixed utsname struct here and just copy it.
+
+.rodata
+
+utsdata:
+        ; sysname
+        .asciiz         "cc65"
+
+        ; nodename
+        .asciiz         ""
+
+        ; release
+        .byte           .string (>.version)
+        .byte           '.'
+        .byte           .string (<.version)
+        .byte           $00
+
+        ; version
+        .byte           '0'     ; unused
+        .byte           $00
+
+        ; machine
+        .asciiz         "Agat"
+
diff --git a/libsrc/apple2/sysuname.s b/libsrc/apple2/sysuname.s
index cd41eac29..52a7ec7e1 100644
--- a/libsrc/apple2/sysuname.s
+++ b/libsrc/apple2/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/atari/sysuname.s b/libsrc/atari/sysuname.s
index 25a891a1b..893ebcfdc 100644
--- a/libsrc/atari/sysuname.s
+++ b/libsrc/atari/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/atari5200/sysuname.s b/libsrc/atari5200/sysuname.s
index 7fd9281a1..5a75edf04 100644
--- a/libsrc/atari5200/sysuname.s
+++ b/libsrc/atari5200/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/atmos/sysuname.s b/libsrc/atmos/sysuname.s
index 546f942ab..7e7bd2341 100644
--- a/libsrc/atmos/sysuname.s
+++ b/libsrc/atmos/sysuname.s
@@ -23,23 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .if             ((.VERSION >> 4) & $0F) > 9
-        .byte           ((.VERSION >> 4) & $0F) / 10 + '0'
-        .byte           ((.VERSION >> 4) & $0F) .MOD 10 + '0'
-        .else
-        .byte           ((.VERSION >> 4) & $0F) + '0'
-        .endif
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .if             (.VERSION & $0F) > 9
-        .byte           (.VERSION & $0F) / 10 + '0'
-        .byte           (.VERSION & $0F) .MOD 10 + '0'
-        .else
-        .byte           (.VERSION & $0F) + '0'
-        .endif
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/c128/sysuname.s b/libsrc/c128/sysuname.s
index 55fe5ba28..b7c7794b5 100644
--- a/libsrc/c128/sysuname.s
+++ b/libsrc/c128/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/c16/sysuname.s b/libsrc/c16/sysuname.s
index c44ab6acc..960509866 100644
--- a/libsrc/c16/sysuname.s
+++ b/libsrc/c16/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/c64/sysuname.s b/libsrc/c64/sysuname.s
index 1903986c9..1f6cfc410 100644
--- a/libsrc/c64/sysuname.s
+++ b/libsrc/c64/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/cbm510/sysuname.s b/libsrc/cbm510/sysuname.s
index 24d4dc03b..579908d19 100644
--- a/libsrc/cbm510/sysuname.s
+++ b/libsrc/cbm510/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/cbm610/sysuname.s b/libsrc/cbm610/sysuname.s
index 984cb93df..dab807a4f 100644
--- a/libsrc/cbm610/sysuname.s
+++ b/libsrc/cbm610/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/creativision/sysuname.s b/libsrc/creativision/sysuname.s
index 725cb2a62..43a0c7659 100644
--- a/libsrc/creativision/sysuname.s
+++ b/libsrc/creativision/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/cx16/sysuname.s b/libsrc/cx16/sysuname.s
index 4aefb7cf5..06f4d7662 100644
--- a/libsrc/cx16/sysuname.s
+++ b/libsrc/cx16/sysuname.s
@@ -24,13 +24,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/geos-common/system/sysuname.s b/libsrc/geos-common/system/sysuname.s
index 8eac05941..954e5be5e 100644
--- a/libsrc/geos-common/system/sysuname.s
+++ b/libsrc/geos-common/system/sysuname.s
@@ -22,14 +22,14 @@ utsdata:
         .asciiz ""
 
         ; release
-        .byte ((.VERSION >> 8) & $0F) + '0'
-        .byte '.'
-        .byte ((.VERSION >> 4) & $0F) + '0'
-        .byte $00
+        .byte           .string (>.version)
+        .byte           '.'
+        .byte           .string (<.version)
+        .byte           $00
 
         ; version
-        .byte (.VERSION & $0F) + '0'
-        .byte $00
+        .byte           '0'     ; unused
+        .byte           $00
 
         ; machine
         .asciiz "GEOS"
diff --git a/libsrc/lynx/sysuname.s b/libsrc/lynx/sysuname.s
index 879297ea4..3c75fac08 100644
--- a/libsrc/lynx/sysuname.s
+++ b/libsrc/lynx/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/nes/sysuname.s b/libsrc/nes/sysuname.s
index fcab503e1..7e72df358 100644
--- a/libsrc/nes/sysuname.s
+++ b/libsrc/nes/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/pet/sysuname.s b/libsrc/pet/sysuname.s
index 59174d821..ddc7d644f 100644
--- a/libsrc/pet/sysuname.s
+++ b/libsrc/pet/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/plus4/sysuname.s b/libsrc/plus4/sysuname.s
index 332daae0d..e75e6cacc 100644
--- a/libsrc/plus4/sysuname.s
+++ b/libsrc/plus4/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/telestrat/sysuname.s b/libsrc/telestrat/sysuname.s
index 51af1d8fe..09aaff831 100644
--- a/libsrc/telestrat/sysuname.s
+++ b/libsrc/telestrat/sysuname.s
@@ -23,23 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .if             ((.VERSION >> 4) & $0F) > 9
-        .byte           ((.VERSION >> 4) & $0F) / 10 + '0'
-        .byte           ((.VERSION >> 4) & $0F) .MOD 10 + '0'
-        .else
-        .byte           ((.VERSION >> 4) & $0F) + '0'
-        .endif
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .if             (.VERSION & $0F) > 9
-        .byte           (.VERSION & $0F) / 10 + '0'
-        .byte           (.VERSION & $0F) .MOD 10 + '0'
-        .else
-        .byte           (.VERSION & $0F) + '0'
-        .endif
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/libsrc/vic20/sysuname.s b/libsrc/vic20/sysuname.s
index 18d5db9a9..43ee37896 100644
--- a/libsrc/vic20/sysuname.s
+++ b/libsrc/vic20/sysuname.s
@@ -23,13 +23,13 @@ utsdata:
         .asciiz         ""
 
         ; release
-        .byte           ((.VERSION >> 8) & $0F) + '0'
+        .byte           .string (>.version)
         .byte           '.'
-        .byte           ((.VERSION >> 4) & $0F) + '0'
+        .byte           .string (<.version)
         .byte           $00
 
         ; version
-        .byte           (.VERSION & $0F) + '0'
+        .byte           '0'     ; unused
         .byte           $00
 
         ; machine
diff --git a/samples/Makefile b/samples/Makefile
index 267e253ff..c0b198a9d 100644
--- a/samples/Makefile
+++ b/samples/Makefile
@@ -322,8 +322,7 @@ EXELIST_gamate =   \
         hello
 
 EXELIST_geos-cbm = \
-        ascii      \
-        diodemo
+        ascii
 
 EXELIST_geos-apple = \
         ascii
@@ -382,6 +381,9 @@ EXELIST_sim6502 =  \
 
 EXELIST_sim65c02 = $(EXELIST_sim6502)
 
+EXELIST_rp6502 = \
+        notavailable
+
 EXELIST_supervision = \
         notavailable
 
@@ -450,6 +452,7 @@ TARGETS :=     \
   atarixl      \
   atari2600    \
   atari5200    \
+  atari7800    \
   atmos        \
   bbc          \
   c128         \
@@ -461,6 +464,8 @@ TARGETS :=     \
   creativision \
   cx16         \
   gamate       \
+  geos-apple   \
+  geos-cbm     \
   kim1         \
   lunix        \
   lynx         \
@@ -470,6 +475,7 @@ TARGETS :=     \
   pce          \
   pet          \
   plus4        \
+  rp6502       \
   sim6502      \
   sim65c02     \
   supervision  \
@@ -477,12 +483,14 @@ TARGETS :=     \
   telestrat    \
   vic20
 
+
 # --------------------------------------------------------------------------
 # Rule to make the binaries for every platform
 
 define TARGET_recipe
 
 @echo making samples for: $(T)
+@$(MAKE) --no-print-directory clean SYS:=$(T)
 @$(MAKE) -j2 SYS:=$(T)
 @$(MAKE) --no-print-directory clean SYS:=$(T)
 
diff --git a/samples/checkversion.c b/samples/checkversion.c
index f2a9d4a49..9d88cecd3 100644
--- a/samples/checkversion.c
+++ b/samples/checkversion.c
@@ -9,6 +9,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <sys/utsname.h>
 
 #if ((__CC65__ >> 8) > 3) || ((__CC65__ & 0x000f) > 0)
 /* compiler version is 2.19-git or higher */
@@ -29,6 +30,17 @@
 
 int main(void)
 {
+#if !defined(__SIM6502__) && !defined(__SIM65C02__) && !defined(__AGAT__)
+    struct utsname buf;
+    uname (&buf);
+
+    printf("utsname.sysname: %s\n", buf.sysname);
+    printf("utsname.nodename: %s\n", buf.nodename);
+    printf("utsname.release: %s\n", buf.release);
+    printf("utsname.version: %s\n", buf.version);
+    printf("utsname.machine: %s\n", buf.machine);
+#endif
+
     printf("__CC65__ defined as %04x\n", __CC65__);
     printf("compiler version is %u.%u\n", VER_MAJOR, VER_MINOR);
     if (__CC65__ == VERSION) {
diff --git a/samples/tutorial/Makefile b/samples/tutorial/Makefile
index 7b3286e27..685c8dd69 100644
--- a/samples/tutorial/Makefile
+++ b/samples/tutorial/Makefile
@@ -43,6 +43,9 @@ EXELIST_atari2600 = \
 EXELIST_atari5200 = \
 	notavailable
 
+EXELIST_atari7800 = \
+	notavailable
+
 EXELIST_bbc = \
 	notavailable
 
diff --git a/src/cc65/codeopt.c b/src/cc65/codeopt.c
index e3869d786..988e2d770 100644
--- a/src/cc65/codeopt.c
+++ b/src/cc65/codeopt.c
@@ -133,6 +133,7 @@ static OptFunc DOptCmp2         = { OptCmp2,         "OptCmp2",          85, 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 };
@@ -255,6 +256,7 @@ static OptFunc* OptFuncs[] = {
     &DOptCmp3,
     &DOptCmp4,
     &DOptCmp5,
+    &DOptCmp6,
     &DOptCmp7,
     &DOptCmp8,
     &DOptCmp9,
@@ -729,6 +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, &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 eb138e78d..41245b58d 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.
diff --git a/src/cc65/coptcmp.h b/src/cc65/coptcmp.h
index 98e75715b..268e55be2 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.