iodbc is myodbc-2.50.5
mysql is mysql-3.21.22-beta

nothing else compiled in. Here is the session:

be@shelley:~/php-fi/work $ ./php
<?php
 
   $conn=odbc_connect("mysql","","");
   $cursor=odbc_cursor($conn);
Segmentation Fault (core dumped)

be@shelley:~/php-fi/work $ gdb php core

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GDB 4.16 (sparc-sun-solaris2.5.1), Copyright 1996 Free Software Foundation, Inc...
Core was generated by `./php'.
Program terminated with signal 11, Segmentation fault.
Reading symbols from /usr/lib/libm.so.1...done.
Reading symbols from /usr/lib/libdl.so.1...done.
Reading symbols from /usr/lib/libnsl.so.1...done.
Reading symbols from /usr/lib/libsocket.so.1...done.
Reading symbols from /usr/lib/libc.so.1...done.
Reading symbols from /usr/lib/libintl.so.1...done.
Reading symbols from /usr/lib/libmp.so.1...done.
Reading symbols from /usr/lib/libw.so.1...done.
Reading symbols from /opt/mysql/lib/libmyodbc_mysql.so...done.
Reading symbols from /usr/lib/nss_files.so.1...done.
#0  0xef623d78 in strlen ()
(gdb) bt
#0  0xef623d78 in strlen ()
#1  0x2a274 in format_converter (odp=0xefffd548, fmt=0x66415 "s", ap=0xefffdea0) at snprintf.c:732
#2  0x2a654 in strx_printv (ccp=0xefffd5c4, buf=0xefffda40 "Unable to find result index ", len=1022, format=0x66415 "s", ap=0xefffdea0) at snprintf.c:906
#3  0x2a6dc in ap_vsnprintf (buf=0xefffda40 "Unable to find result index ", len=1023, format=0x663f8 "Unable to find result index %s", ap=0xefffde9c)
    at snprintf.c:930
#4  0x2142c in php3_error (type=2, format=0x663f8 "Unable to find result index %s") at main.c:313
#5  0x43b10 in php3_uodbc_cursor (ht=0x0, return_value=0x7bb60, list=0x7bb80, plist=0x7bbac) at functions/unified_odbc.c:756
#6  0x1b2a4 in cs_functioncall_post_variable_passing (function_name=0xefffe1b0) at control_structures_inline.h:837
#7  0x1db54 in phpparse () at language-parser.y:443
#8  0x22afc in php3_parse (yyin=0x8c3f8) at main.c:1209
#9  0x23160 in main (argc=1, argv=0xeffffd34) at main.c:1426
(gdb)
be@shelley:~/php-fi/work $