Bug#53445: Build with -Wall and fix warnings that it generates

Apart strict-aliasing warnings, fix the remaining warnings
generated by GCC 4.4.4 -Wall and -Wextra flags.

One major source of warnings was the in-house function my_bcmp
which (unconventionally) took pointers to unsigned characters
as the byte sequences to be compared. Since my_bcmp and bcmp
are deprecated functions whose only difference with memcmp is
the return value, every use of the function is replaced with
memcmp as the special return value wasn't actually being used
by any caller.

There were also various other warnings, mostly due to type
mismatches, missing return values, missing prototypes, dead
code (unreachable) and ignored return values.

3 files changed, 14 insertions, 44 deletions

diff --git a/include/m_string.h b/include/m_string.h
index b2a1d9ff2f4..d027047f501 100644
--- a/include/m_string.h
+++ b/include/m_string.h
@@ -33,10 +33,6 @@
 /* need by my_vsnprintf */
 #include <stdarg.h> 
 
-#ifdef _AIX
-#undef HAVE_BCMP
-#endif
-
 /*  This is needed for the definitions of bzero... on solaris */
 #if defined(HAVE_STRINGS_H)
 #include <strings.h>
@@ -60,14 +56,6 @@
 /* Unixware 7 */
 #if !defined(HAVE_BFILL)
 # define bfill(A,B,C)           memset((A),(C),(B))
-# define bmove_align(A,B,C)    memcpy((A),(B),(C))
-#endif
-
-#if !defined(HAVE_BCMP)
-# define bcopy(s, d, n)		memcpy((d), (s), (n))
-# define bcmp(A,B,C)		memcmp((A),(B),(C))
-# define bzero(A,B)		memset((A),0,(B))
-# define bmove_align(A,B,C)     memcpy((A),(B),(C))
 #endif
 
 #if defined(__cplusplus)
@@ -120,15 +108,6 @@ extern	void bfill(uchar *dst,size_t len,pchar fill);
 extern	void bzero(uchar * dst,size_t len);
 #endif
 
-#if !defined(bcmp) && !defined(HAVE_BCMP)
-extern	size_t bcmp(const uchar *s1,const uchar *s2,size_t len);
-#endif
-#ifdef HAVE_purify
-extern	size_t my_bcmp(const uchar *s1,const uchar *s2,size_t len);
-#undef bcmp
-#define bcmp(A,B,C) my_bcmp((A),(B),(C))
-#endif /* HAVE_purify */
-
 #ifndef bmove512
 extern	void bmove512(uchar *dst,const uchar *src,size_t len);
 #endif
diff --git a/include/my_bitmap.h b/include/my_bitmap.h
index 78642df3362..ab69b2d671d 100644
--- a/include/my_bitmap.h
+++ b/include/my_bitmap.h
@@ -159,22 +159,6 @@ static inline my_bool bitmap_cmp(const MY_BITMAP *map1, const MY_BITMAP *map2)
 #define bitmap_set_all(MAP) \
   (memset((MAP)->bitmap, 0xFF, 4*no_words_in_map((MAP))))
 
-/**
-   check, set and clear a bit of interest of an integer.
-
-   If the bit is out of range @retval -1. Otherwise
-   bit_is_set   @return 0 or 1 reflecting the bit is set or not;
-   bit_do_set   @return 1 (bit is set 1)
-   bit_do_clear @return 0 (bit is cleared to 0)
-*/
-
-#define bit_is_set(I,B)   (sizeof(I) * CHAR_BIT > (B) ?                 \
-                           (((I) & (ULL(1) << (B))) == 0 ? 0 : 1) : -1)
-#define bit_do_set(I,B)   (sizeof(I) * CHAR_BIT > (B) ?         \
-                           ((I) |= (ULL(1) << (B)), 1) : -1)
-#define bit_do_clear(I,B) (sizeof(I) * CHAR_BIT > (B) ?         \
-                           ((I) &= ~(ULL(1) << (B)), 0) : -1)
-
 #ifdef	__cplusplus
 }
 #endif
diff --git a/include/my_global.h b/include/my_global.h
index e13c7c37b62..572df6a584d 100644
--- a/include/my_global.h
+++ b/include/my_global.h
@@ -556,22 +556,30 @@ int	__void__;
 #endif
 #endif /* DONT_DEFINE_VOID */
 
-#if defined(_lint) || defined(FORCE_INIT_OF_VARS)
-#define LINT_INIT(var)	var=0			/* No uninitialize-warning */
+/*
+  Deprecated workaround for false-positive uninitialized variables
+  warnings. Those should be silenced using tool-specific heuristics.
+
+  Enabled by default for g++ due to the bug referenced below.
+*/
+#if defined(_lint) || defined(FORCE_INIT_OF_VARS) || \
+    (defined(__GNUC__) && defined(__cplusplus))
+#define LINT_INIT(var) var= 0
 #else
 #define LINT_INIT(var)
 #endif
 
-/* 
+/*
    Suppress uninitialized variable warning without generating code.
 
    The _cplusplus is a temporary workaround for C++ code pending a fix
-   for a g++ bug (http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34772). 
+   for a g++ bug (http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34772).
 */
-#if defined(_lint) || defined(FORCE_INIT_OF_VARS) || defined(__cplusplus) || \
-  !defined(__GNUC__)
+#if defined(_lint) || defined(FORCE_INIT_OF_VARS) || \
+    defined(__cplusplus) || !defined(__GNUC__)
 #define UNINIT_VAR(x) x= 0
 #else
+/* GCC specific self-initialization which inhibits the warning. */
 #define UNINIT_VAR(x) x= x
 #endif
 
@@ -595,7 +603,6 @@ typedef unsigned short ushort;
 #define set_if_bigger(a,b)  do { if ((a) < (b)) (a)=(b); } while(0)
 #define set_if_smaller(a,b) do { if ((a) > (b)) (a)=(b); } while(0)
 #define test_all_bits(a,b) (((a) & (b)) == (b))
-#define set_bits(type, bit_count) (sizeof(type)*8 <= (bit_count) ? ~(type) 0 : ((((type) 1) << (bit_count)) - (type) 1))
 #define array_elements(A) ((uint) (sizeof(A)/sizeof(A[0])))
 
 /* Define some general constants */