build: add const and pure attributes, per gcc recommendation

* src/mkid.c (ceil_log_8, ceil_log_2): Add "const" attribute.
(token_hash_1, token_hash_2): Add "pure" attribute.
(token_hash_cmp, token_qsort_cmp): Likewise.
(count_vec_size, count_buf_size): Likewise.

* libidu/idu-hash.c (round_up_2): Add "const" attribute.
* libidu/scanners.h (get_language): Add "pure" attribute.
* libidu/idfile.h (token_flags): Likewise.
(token_count): Likewise.
(member_file_qsort_compare): Likewise.
(tree8_count_levels): Add "const" attribute.
* libidu/walker.c (symlink_ancestry): Add "pure" attribute.
(links_depth): Likewise.
(file_link_hash_1): Likewise.
(vector_length): Likewise.
(file_link_hash_compare): Likewise.
(string_in_vector): Likewise.
* src/lid.c (vector_cardinality, get_radix, dtoi, otoi): Likewise.
(is_regexp): Likewise.
(vector_length): Remove forward decl and move function definition
to precede first use.

2 files changed, 15 insertions, 15 deletions

diff --git a/src/lid.c b/src/lid.c
index 9a5054b..cd307c0 100644
--- a/src/lid.c
+++ b/src/lid.c
@@ -810,7 +810,7 @@ report_nothing (char const *name, struct file_link **flinkv ATTRIBUTE_UNUSED)
     puts (name);
 }
 
-static int
+static int _GL_ATTRIBUTE_PURE
 vector_cardinality (void *vector)
 {
   void **v = (void **) vector;
@@ -1239,7 +1239,7 @@ query_binary_search (char const *token_0)
 
 /* Are there any regexp meta-characters in name?? */
 
-static int
+static int _GL_ATTRIBUTE_PURE
 is_regexp (char *name)
 {
   int backslash = 0;
@@ -1284,7 +1284,7 @@ has_right_delimiter (char const *pattern)
 
 /* Does `name' occur in `line' delimited by non-alphanumerics?? */
 
-static int
+static int _GL_ATTRIBUTE_PURE
 word_match (char const *name_0, char const *line)
 {
   char const *name = name_0;
@@ -1319,7 +1319,7 @@ word_match (char const *name_0, char const *line)
    apply.  In particular, it is impossible to determine the radix of
    0, so return all possibilities.  */
 
-static int
+static int _GL_ATTRIBUTE_PURE
 get_radix (char const *str)
 {
   if (!isdigit (*str))
@@ -1374,7 +1374,7 @@ stoi (char const *str)
 
 /* Convert an ascii octal number to an integer. */
 
-static int
+static int _GL_ATTRIBUTE_PURE
 otoi (char const *str)
 {
   int n = 0;
@@ -1391,7 +1391,7 @@ otoi (char const *str)
 
 /* Convert an ascii decimal number to an integer. */
 
-static int
+static int _GL_ATTRIBUTE_PURE
 dtoi (char const *str)
 {
   int n = 0;
@@ -1408,7 +1408,7 @@ dtoi (char const *str)
 
 /* Convert an ascii hex number to an integer. */
 
-static int
+static int _GL_ATTRIBUTE_PURE
 xtoi (char const *str)
 {
   int n = 0;
diff --git a/src/mkid.c b/src/mkid.c
index 821e8d3..082395e 100644
--- a/src/mkid.c
+++ b/src/mkid.c
@@ -443,7 +443,7 @@ main (int argc, char **argv)
 
 /* Return the integer ceiling of the base-8 logarithm of N.  */
 
-static int
+static int _GL_ATTRIBUTE_CONST
 ceil_log_8 (unsigned long n)
 {
   int log_8 = 0;
@@ -459,7 +459,7 @@ ceil_log_8 (unsigned long n)
 
 /* Return the integer ceiling of the base-2 logarithm of N.  */
 
-static int
+static int _GL_ATTRIBUTE_CONST
 ceil_log_2 (unsigned long n)
 {
   int log_2 = 0;
@@ -782,26 +782,26 @@ write_id_file (struct idhead *idhp)
 /* Define primary and secondary hash and comparison functions for the
    token table.  */
 
-static unsigned long
+static unsigned long _GL_ATTRIBUTE_PURE
 token_hash_1 (void const *key)
 {
   return_STRING_HASH_1 (TOKEN_NAME ((struct token const *) key));
 }
 
-static unsigned long
+static unsigned long _GL_ATTRIBUTE_PURE
 token_hash_2 (void const *key)
 {
   return_STRING_HASH_2 (TOKEN_NAME ((struct token const *) key));
 }
 
-static int
+static int _GL_ATTRIBUTE_PURE
 token_hash_cmp (void const *x, void const *y)
 {
   return_STRING_COMPARE (TOKEN_NAME ((struct token const *) x),
 			 TOKEN_NAME ((struct token const *) y));
 }
 
-static int
+static int _GL_ATTRIBUTE_PURE
 token_qsort_cmp (void const *x, void const *y)
 {
   return_STRING_COMPARE (TOKEN_NAME (*(struct token const *const *) x),
@@ -938,7 +938,7 @@ make_sibling_summary (struct summary *summary)
   return summary;
 }
 
-static int
+static int _GL_ATTRIBUTE_PURE
 count_vec_size (struct summary *summary, unsigned char const *tail_hits)
 {
   struct summary **kids;
@@ -962,7 +962,7 @@ count_vec_size (struct summary *summary, unsigned char const *tail_hits)
     }
 }
 
-static int
+static int _GL_ATTRIBUTE_PURE
 count_buf_size (struct summary *summary, unsigned char const *tail_hits)
 {
   struct summary **kids;