avoid warnings about initialization of automatic aggregates

* src/system.h (DZA_CONCAT0, DZA_CONCAT): New macros.
(DECLARE_ZEROED_AGGREGATE): New macro.
* src/ls.c (quote_name): Use it.
* src/pathchk.c (portable_chars_only): Use it.
* src/shred.c (main): Use it.
* src/stty.c (main): Use it.
* src/wc.c (SUPPORT_OLD_MBRTOWC): Use it.

6 files changed, 19 insertions, 6 deletions

diff --git a/src/ls.c b/src/ls.c
index 7619cebc1..008186595 100644
--- a/src/ls.c
+++ b/src/ls.c
@@ -3721,7 +3721,7 @@ quote_name (FILE *out, const char *name, struct quoting_options const *options,
 		     reach its end, replacing each non-printable multibyte
 		     character with a single question mark.  */
 		  {
-		    mbstate_t mbstate = { 0, };
+		    DECLARE_ZEROED_AGGREGATE (mbstate_t, mbstate);
 		    do
 		      {
 			wchar_t wc;
diff --git a/src/pathchk.c b/src/pathchk.c
index 48001fc03..3b2bd467b 100644
--- a/src/pathchk.c
+++ b/src/pathchk.c
@@ -198,7 +198,7 @@ portable_chars_only (char const *file, size_t filelen)
 
   if (*invalid)
     {
-      mbstate_t mbstate = { 0, };
+      DECLARE_ZEROED_AGGREGATE (mbstate_t, mbstate);
       size_t charlen = mbrlen (invalid, filelen - validlen, &mbstate);
       error (0, 0,
 	     _("nonportable character %s in file name %s"),
diff --git a/src/shred.c b/src/shred.c
index 6b7d90167..1e7bffb90 100644
--- a/src/shred.c
+++ b/src/shred.c
@@ -1099,7 +1099,7 @@ int
 main (int argc, char **argv)
 {
   bool ok = true;
-  struct Options flags = { 0, };
+  DECLARE_ZEROED_AGGREGATE (struct Options, flags);
   char **file;
   int n_files;
   int c;
diff --git a/src/stty.c b/src/stty.c
index 8eeaa2fed..eb4f30f07 100644
--- a/src/stty.c
+++ b/src/stty.c
@@ -726,7 +726,7 @@ main (int argc, char **argv)
 {
   /* Initialize to all zeroes so there is no risk memcmp will report a
      spurious difference in an uninitialized portion of the structure.  */
-  struct termios mode = { 0, };
+  DECLARE_ZEROED_AGGREGATE (struct termios, mode);
 
   enum output_type output_type;
   int optc;
@@ -999,7 +999,7 @@ main (int argc, char **argv)
     {
       /* Initialize to all zeroes so there is no risk memcmp will report a
 	 spurious difference in an uninitialized portion of the structure.  */
-      struct termios new_mode = { 0, };
+      DECLARE_ZEROED_AGGREGATE (struct termios, new_mode);
 
       if (tcsetattr (STDIN_FILENO, TCSADRAIN, &mode))
 	error (EXIT_FAILURE, errno, "%s", device_name);
diff --git a/src/system.h b/src/system.h
index d51caedf1..21182a47f 100644
--- a/src/system.h
+++ b/src/system.h
@@ -513,6 +513,19 @@ enum
 # define IF_LINT(Code) /* empty */
 #endif
 
+/* With -Dlint, avoid warnings from gcc about code like mbstate_t m = {0,};
+   by wasting space on a static variable of the same type, that is thus
+   guaranteed to be initialized to 0, and use that on the RHS.  */
+#define DZA_CONCAT0(x,y) x ## y
+#define DZA_CONCAT(x,y) DZA_CONCAT0 (x, y)
+#ifdef lint
+# define DECLARE_ZEROED_AGGREGATE(Type, Var) \
+   static Type DZA_CONCAT (s0_, __LINE__); Type Var = DZA_CONCAT (s0_, __LINE__)
+#else
+# define DECLARE_ZEROED_AGGREGATE(Type, Var) \
+  Type Var = { 0, }
+#endif
+
 #ifndef __attribute__
 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8)
 #  define __attribute__(x) /* empty */
diff --git a/src/wc.c b/src/wc.c
index 8cfd974ca..ad25ed8d0 100644
--- a/src/wc.c
+++ b/src/wc.c
@@ -275,7 +275,7 @@ wc (int fd, char const *file_x, struct fstatus *fstatus)
     {
       bool in_word = false;
       uintmax_t linepos = 0;
-      mbstate_t state = { 0, };
+      DECLARE_ZEROED_AGGREGATE (mbstate_t, state);
       bool in_shift = false;
 # if SUPPORT_OLD_MBRTOWC
       /* Back-up the state before each multibyte character conversion and