Omit IF_LINT code that no longer seems needed

Nowadays GCC is smarter, or the Emacs code has mutated, or both,
and now is as good a time as any to remove uses of IF_LINT that
now seem to be unnecessary.
* lib-src/emacsclient.c (set_local_socket):
* lib-src/movemail.c (main) [MAIL_USE_MAILLOCK && HAVE_TOUCHLOCK]:
* src/buffer.c (fix_start_end_in_overlays, fix_overlays_before):
* src/casefiddle.c (casify_region):
* src/charset.c (load_charset_map):
* src/coding.c (decode_coding_object, encode_coding_object):
* src/data.c (Fmake_variable_buffer_local, Fmake_local_variable)
(cons_to_unsigned, cons_to_signed):
* src/frame.c (make_frame, x_set_frame_parameters):
* src/keyboard.c (read_event_from_main_queue):
* src/regex.c (regex_compile):
* src/syntax.c (back_comment):
* src/window.c (Frecenter):
* src/xfaces.c (Fx_list_fonts):
Remove IF_LINT that no longer seems necessary.
* src/image.c (png_load_body, jpeg_load_body): Simplify use of IF_LINT.
* src/keyboard.c (read_char): Use IF_LINT (volatile) rather than
a pragma dance to pacify GCC -Wclobbered.
* src/xdisp.c (x_produce_glyphs): Rewrite to avoid need for IF_LINT.

* src/xterm.c (x_connection_closed): Now _Noreturn, which should
mean we do not need IF_LINT any more.
(x_io_error_quitter): Now _Noreturn.  Put an 'assume (false)’
at the end, to forestall warnings from older compilers.

1 files changed, 6 insertions, 14 deletions

diff --git a/src/image.c b/src/image.c
index c1f25aa2357..0991f579579 100644
--- a/src/image.c
+++ b/src/image.c
@@ -5895,12 +5895,13 @@ static bool
 png_load_body (struct frame *f, struct image *img, struct png_load_context *c)
 {
   Lisp_Object specified_file;
-  Lisp_Object specified_data;
+  /* IF_LINT (volatile) works around GCC bug 54561.  */
+  Lisp_Object IF_LINT (volatile) specified_data;
+  FILE * IF_LINT (volatile) fp = NULL;
   int x, y;
   ptrdiff_t i;
   png_struct *png_ptr;
   png_info *info_ptr = NULL, *end_info = NULL;
-  FILE *fp = NULL;
   png_byte sig[8];
   png_byte *pixels = NULL;
   png_byte **rows = NULL;
@@ -5922,7 +5923,6 @@ png_load_body (struct frame *f, struct image *img, struct png_load_context *c)
   /* Find out what file to load.  */
   specified_file = image_spec_value (img->spec, QCfile, NULL);
   specified_data = image_spec_value (img->spec, QCdata, NULL);
-  IF_LINT (Lisp_Object volatile specified_data_volatile = specified_data);
 
   if (NILP (specified_data))
     {
@@ -6018,10 +6018,6 @@ png_load_body (struct frame *f, struct image *img, struct png_load_context *c)
       return 0;
     }
 
-  /* Silence a bogus diagnostic; see GCC bug 54561.  */
-  IF_LINT (fp = c->fp);
-  IF_LINT (specified_data = specified_data_volatile);
-
   /* Read image info.  */
   if (!NILP (specified_data))
     png_set_read_fn (png_ptr, &tbr, png_read_from_memory);
@@ -6672,9 +6668,9 @@ jpeg_load_body (struct frame *f, struct image *img,
                 struct my_jpeg_error_mgr *mgr)
 {
   Lisp_Object specified_file;
-  Lisp_Object specified_data;
-  /* The 'volatile' silences a bogus diagnostic; see GCC bug 54561.  */
-  FILE * IF_LINT (volatile) fp = NULL;
+  /* IF_LINT (volatile) works around GCC bug 54561.  */
+  Lisp_Object IF_LINT (volatile) specified_data;
+  FILE *volatile fp = NULL;
   JSAMPARRAY buffer;
   int row_stride, x, y;
   unsigned long *colors;
@@ -6687,7 +6683,6 @@ jpeg_load_body (struct frame *f, struct image *img,
   /* Open the JPEG file.  */
   specified_file = image_spec_value (img->spec, QCfile, NULL);
   specified_data = image_spec_value (img->spec, QCdata, NULL);
-  IF_LINT (Lisp_Object volatile specified_data_volatile = specified_data);
 
   if (NILP (specified_data))
     {
@@ -6751,9 +6746,6 @@ jpeg_load_body (struct frame *f, struct image *img,
       return 0;
     }
 
-  /* Silence a bogus diagnostic; see GCC bug 54561.  */
-  IF_LINT (specified_data = specified_data_volatile);
-
   /* Create the JPEG decompression object.  Let it read from fp.
          Read the JPEG image header.  */
   jpeg_CreateDecompress (&mgr->cinfo, JPEG_LIB_VERSION, sizeof *&mgr->cinfo);