(setup_coding_system): For invalid coding-system, set

coding->eol_type to CODING_EOL_UNDECIDED.
(encode_coding): Cancel previous change.
(shrink_encoding_region): Likewise.
(code_convert_region1): Likewise.
(code_convert_string1): Likewise.
(code_convert_string_norecord): Likewise.

1 files changed, 8 insertions, 11 deletions

diff --git a/src/coding.c b/src/coding.c
index bd96b5cc068..155da568007 100644
--- a/src/coding.c
+++ b/src/coding.c
@@ -384,7 +384,9 @@ Lisp_Object eol_mnemonic_unix, eol_mnemonic_dos, eol_mnemonic_mac;
 Lisp_Object eol_mnemonic_undecided;
 
 /* Format of end-of-line decided by system.  This is CODING_EOL_LF on
-   Unix, CODING_EOL_CRLF on DOS/Windows, and CODING_EOL_CR on Mac.  */
+   Unix, CODING_EOL_CRLF on DOS/Windows, and CODING_EOL_CR on Mac.
+   This has an effect only for external encoding (i.e. for output to
+   file and process), not for in-buffer or Lisp string encoding.  */
 int system_eol_type;
 
 #ifdef emacs
@@ -3924,10 +3926,7 @@ setup_coding_system (coding_system, coding)
   coding->type = coding_type_no_conversion;
   coding->category_idx = CODING_CATEGORY_IDX_BINARY;
   coding->common_flags = 0;
-  coding->eol_type = NILP (coding_system) ? system_eol_type : CODING_EOL_LF;
-  if (coding->eol_type != CODING_EOL_LF)
-    coding->common_flags
-      |= CODING_REQUIRE_DECODING_MASK | CODING_REQUIRE_ENCODING_MASK;
+  coding->eol_type = CODING_EOL_UNDECIDED;
   coding->pre_write_conversion = coding->post_read_conversion = Qnil;
   return NILP (coding_system) ? 0 : -1;
 }
@@ -5004,7 +5003,7 @@ encode_coding (coding, source, destination, src_bytes, dst_bytes)
   coding->errors = 0;
   coding->result = CODING_FINISH_NORMAL;
   if (coding->eol_type == CODING_EOL_UNDECIDED)
-    coding->eol_type = system_eol_type;
+    coding->eol_type = CODING_EOL_LF;
 
   switch (coding->type)
     {
@@ -5261,8 +5260,6 @@ shrink_encoding_region (beg, end, coding, str)
   if (coding->type == coding_type_ccl
       || coding->eol_type == CODING_EOL_CRLF
       || coding->eol_type == CODING_EOL_CR
-      || (coding->eol_type == CODING_EOL_UNDECIDED
-          && system_eol_type != CODING_EOL_LF)
       || (coding->cmp_data && coding->cmp_data->used > 0))
     {
       /* We can't skip any data.  */
@@ -7118,7 +7115,7 @@ code_convert_region1 (start, end, coding_system, encodep)
   from = XFASTINT (start);
   to = XFASTINT (end);
 
-  if (NILP (coding_system) && system_eol_type == CODING_EOL_LF)
+  if (NILP (coding_system))
     return make_number (to - from);
 
   if (setup_coding_system (Fcheck_coding_system (coding_system), &coding) < 0)
@@ -7173,7 +7170,7 @@ code_convert_string1 (string, coding_system, nocopy, encodep)
   CHECK_STRING (string);
   CHECK_SYMBOL (coding_system);
 
-  if (NILP (coding_system) && system_eol_type == CODING_EOL_LF)
+  if (NILP (coding_system))
     return (NILP (nocopy) ? Fcopy_sequence (string) : string);
 
   if (setup_coding_system (Fcheck_coding_system (coding_system), &coding) < 0)
@@ -7232,7 +7229,7 @@ code_convert_string_norecord (string, coding_system, encodep)
   CHECK_STRING (string);
   CHECK_SYMBOL (coding_system);
 
-  if (NILP (coding_system) && system_eol_type == CODING_EOL_LF)
+  if (NILP (coding_system))
     return string;
 
   if (setup_coding_system (Fcheck_coding_system (coding_system), &coding) < 0)