Fix for bug #31207: Test "join_nested" shows different strategy on IA64

CPUs / Intel's ICC compile

The bug is a combination of two problems:

1. IA64/ICC MySQL binaries use glibc's qsort(), not the one in mysys.

2. The order relation implemented by join_tab_cmp() is not transitive,
i.e. it is possible to choose such a, b and c that (a < b) && (b < c)
but (c < a). This implies that result of a sort using the relation
implemented by join_tab_cmp() depends on the order in which
elements are compared, i.e. the result is implementation-specific. Since
choose_plan() uses qsort() to pre-sort the
join tables using join_tab_cmp() as a compare function, the results of
the sorting may vary depending on qsort() implementation.

It is neither possible nor important to implement a better ordering
algorithm in join_tab_cmp(). Therefore the only way to fix it is to
force our own qsort() to be used by renaming it to my_qsort(), so we don't depend
on linker to decide that.

This patch also "fixes" bug #20530: qsort redefinition violates the
standard.


include/my_sys.h:
  Renamed qsort() and qsort2() to my_qsort() and my_qsort2(). Since
  previously we relied on stdlib.h to provide a declaration for qsort(), a
  separate declaration for my_qsort() is now required.
libmysql/Makefile.shared:
  Added mf_qsort.c to libmysql, since my_lib.c now uses my_qsort() instead of qsort().
myisam/ft_boolean_search.c:
  Replaced qsort2() with my_qsort2().
myisam/ft_nlq_search.c:
  Replaced qsort2() with my_qsort2().
myisam/myisampack.c:
  Replaced qsort() with my_qsort().
myisam/sort.c:
  Replaced qsort2() with my_qsort2().
mysys/mf_keycache.c:
  Replaced qsort() with my_qsort().
mysys/mf_qsort.c:
  Renamed qsort() to my_qsort() and qsort2() to my_qsort2().
mysys/mf_sort.c:
  Replaced qsort2() with my_qsort2().
mysys/my_lib.c:
  Replaced qsort() with my_qsort().
mysys/queues.c:
  Replaced qsort2() with my_qsort2().
sql/item_cmpfunc.cc:
  Replaced qsort2() with my_qsort2().
sql/item_cmpfunc.h:
  Replaced qsort2() with my_qsort2().
sql/opt_range.cc:
  Replaced qsort() with my_qsort().
sql/records.cc:
  Replaced qsort() with my_qsort().
sql/sql_acl.cc:
  Replaced qsort() with my_qsort().
sql/sql_array.h:
  Replaced qsort() with my_qsort().
sql/sql_help.cc:
  Replaced qsort() with my_qsort().
sql/sql_select.cc:
  Replaced qsort() with my_qsort().
sql/examples/ha_tina.cc:
  Replaced qsort() with my_qsort().
sql/sql_table.cc:
  Replaced qsort() with my_qsort().

4 files changed, 11 insertions, 10 deletions

diff --git a/myisam/ft_boolean_search.c b/myisam/ft_boolean_search.c
index 9f442148069..57de75ee4be 100644
--- a/myisam/ft_boolean_search.c
+++ b/myisam/ft_boolean_search.c
@@ -430,8 +430,8 @@ FT_INFO * ft_init_boolean_search(MI_INFO *info, uint keynr, byte *query,
   ftb->list=(FTB_WORD **)alloc_root(&ftb->mem_root,
                                      sizeof(FTB_WORD *)*ftb->queue.elements);
   memcpy(ftb->list, ftb->queue.root+1, sizeof(FTB_WORD *)*ftb->queue.elements);
-  qsort2(ftb->list, ftb->queue.elements, sizeof(FTB_WORD *),
-                              (qsort2_cmp)FTB_WORD_cmp_list, ftb->charset);
+  my_qsort2(ftb->list, ftb->queue.elements, sizeof(FTB_WORD *),
+            (qsort2_cmp)FTB_WORD_cmp_list, ftb->charset);
   if (ftb->queue.elements<2) ftb->with_scan &= ~FTB_FLAG_TRUNC;
   ftb->state=READY;
   return ftb;
diff --git a/myisam/ft_nlq_search.c b/myisam/ft_nlq_search.c
index f63735b7e68..41d145c070f 100644
--- a/myisam/ft_nlq_search.c
+++ b/myisam/ft_nlq_search.c
@@ -281,7 +281,8 @@ FT_INFO *ft_init_nlq_search(MI_INFO *info, uint keynr, byte *query,
 	    &dptr, left_root_right);
 
   if (flags & FT_SORTED)
-    qsort2(dlist->doc, dlist->ndocs, sizeof(FT_DOC), (qsort2_cmp)&FT_DOC_cmp, 0);
+    my_qsort2(dlist->doc, dlist->ndocs, sizeof(FT_DOC), (qsort2_cmp)&FT_DOC_cmp,
+              0);
 
 err:
   delete_tree(&aio.dtree);
diff --git a/myisam/myisampack.c b/myisam/myisampack.c
index 4ead51639f3..fa58211ea88 100644
--- a/myisam/myisampack.c
+++ b/myisam/myisampack.c
@@ -3148,7 +3148,7 @@ static void fakebigcodes(HUFF_COUNTS *huff_counts, HUFF_COUNTS *end_count)
     cur_sort_p= sort_counts;
     while (cur_count_p < end_count_p)
       *(cur_sort_p++)= cur_count_p++;
-    (void) qsort(sort_counts, 256, sizeof(my_off_t*), (qsort_cmp) fakecmp);
+    (void) my_qsort(sort_counts, 256, sizeof(my_off_t*), (qsort_cmp) fakecmp);
 
     /*
       Assign faked counts.
diff --git a/myisam/sort.c b/myisam/sort.c
index f48161b7c8e..c44b05313b0 100644
--- a/myisam/sort.c
+++ b/myisam/sort.c
@@ -649,8 +649,8 @@ static int NEAR_F write_keys(MI_SORT_PARAM *info, register uchar **sort_keys,
   uint sort_length=info->key_length;
   DBUG_ENTER("write_keys");
 
-  qsort2((byte*) sort_keys,count,sizeof(byte*),(qsort2_cmp) info->key_cmp,
-         info);
+  my_qsort2((byte*) sort_keys,count,sizeof(byte*),(qsort2_cmp) info->key_cmp,
+            info);
   if (!my_b_inited(tempfile) &&
       open_cached_file(tempfile, my_tmpdir(info->tmpdir), "ST",
                        DISK_BUFFER_SIZE, info->sort_info->param->myf_rw))
@@ -692,8 +692,8 @@ static int NEAR_F write_keys_varlen(MI_SORT_PARAM *info,
   int err;
   DBUG_ENTER("write_keys_varlen");
 
-  qsort2((byte*) sort_keys,count,sizeof(byte*),(qsort2_cmp) info->key_cmp,
-         info);
+  my_qsort2((byte*) sort_keys,count,sizeof(byte*),(qsort2_cmp) info->key_cmp,
+            info);
   if (!my_b_inited(tempfile) &&
       open_cached_file(tempfile, my_tmpdir(info->tmpdir), "ST",
                        DISK_BUFFER_SIZE, info->sort_info->param->myf_rw))
@@ -735,8 +735,8 @@ static int NEAR_F write_index(MI_SORT_PARAM *info, register uchar **sort_keys,
 {
   DBUG_ENTER("write_index");
 
-  qsort2((gptr) sort_keys,(size_t) count,sizeof(byte*),
-        (qsort2_cmp) info->key_cmp,info);
+  my_qsort2((gptr) sort_keys,(size_t) count,sizeof(byte*),
+            (qsort2_cmp) info->key_cmp,info);
   while (count--)
   {
     if ((*info->key_write)(info,*sort_keys++))