[PATCH] Clean up compiler warnings.

[Eric Blake]

* src/builtin.c (m4_patsubst): Drop dead store.
* src/eval.c (unary_term): Likewise.
* src/input.c (match_input): Likewise.  Also drop useless casts to
void.
* src/symtab.c (symtab_debug): Drop useless casts.
---

A compile run with clang found these issues.

 ChangeLog     |    7 +++++++
 src/builtin.c |    1 -
 src/eval.c    |    3 +--
 src/input.c   |   10 +++++-----
 src/symtab.c  |    5 +----
 5 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index ec3852a..01a45fe 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 2010-08-30  Eric Blake  <address@hidden>

+       Clean up compiler warnings.
+       * src/builtin.c (m4_patsubst): Drop dead store.
+       * src/eval.c (unary_term): Likewise.
+       * src/input.c (match_input): Likewise.  Also drop useless casts to
+       void.
+       * src/symtab.c (symtab_debug): Drop useless casts.
+
        Test previous commit.
        * doc/m4.texinfo (Format): Add a test.
        * NEWS: Document the fix.
diff --git a/src/builtin.c b/src/builtin.c
index 6efa901..4b714f8 100644
--- a/src/builtin.c
+++ b/src/builtin.c
@@ -2130,7 +2130,6 @@ m4_patsubst (struct obstack *obs, int argc, token_data 
**argv)
   length = strlen (victim);

   offset = 0;
-  matchpos = 0;
   while (offset <= length)
     {
       matchpos = re_search (&buf, victim, length,
diff --git a/src/eval.c b/src/eval.c
index 40ca3a2..4c00b19 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -789,12 +789,11 @@ exp_term (eval_token et, int32_t *v1)
 static eval_error
 unary_term (eval_token et, int32_t *v1)
 {
-  eval_token et2 = et;
   eval_error er;

   if (et == PLUS || et == MINUS || et == NOT || et == LNOT)
     {
-      et2 = eval_lex (v1);
+      eval_token et2 = eval_lex (v1);
       if (et2 == ERROR)
         return UNKNOWN_INPUT;

diff --git a/src/input.c b/src/input.c
index 6d8eee1..c16f6f1 100644
--- a/src/input.c
+++ b/src/input.c
@@ -614,14 +614,14 @@ match_input (const char *s, bool consume)
   if (s[1] == '\0')
     {
       if (consume)
-        (void) next_char ();
+        next_char ();
       return true;                      /* short match */
     }

-  (void) next_char ();
-  for (n = 1, t = s++; (ch = peek_input ()) == to_uchar (*s++); )
+  next_char ();
+  for (n = 1, t = s++; peek_input () == to_uchar (*s++); )
     {
-      (void) next_char ();
+      next_char ();
       n++;
       if (*s == '\0')           /* long match */
         {
@@ -883,7 +883,7 @@ next_token (token_data *td, int *line)
       while ((ch = peek_input ()) != CHAR_EOF && (isalnum (ch) || ch == '_'))
         {
           obstack_1grow (&token_stack, ch);
-          (void) next_char ();
+          next_char ();
         }
       type = TOKEN_WORD;
     }
diff --git a/src/symtab.c b/src/symtab.c
index 7012cbe..6519a87 100644
--- a/src/symtab.c
+++ b/src/symtab.c
@@ -374,10 +374,7 @@ symtab_debug (void)
       if (s == NULL)
         xprintf ("Name `%s' is unknown\n", text);

-      if (delete)
-        (void) lookup_symbol (text, SYMBOL_DELETE);
-      else
-        (void) lookup_symbol (text, SYMBOL_INSERT);
+      lookup_symbol (text, delete ? SYMBOL_DELETE : SYMBOL_INSERT);
     }
   symtab_print_list (i++);
 }
-- 
1.7.2.2