Description:
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It's a duplicate of Bug #29852, which I cannot comment because it's marked as "Bogus", which it's not

I'm using iconv() for some charset conversions, and, before converting anything to users' supplied charset, i use iconv() to check whether it would convert flawlessly. And I noticed, that iconv() never returns any error if at least the first character in the array given for conversion, is convertable.

However, i think it's a bug somewhere in PHP, because the iconv(1) console command outputs an error in both similar cases:

rq@sugar:~ $ echo "r?ta" > r
rq@sugar:~ $ iconv -futf-8 -tascii r
riconv: illegal input sequence at position 1
^^ note the "r" here.

rq@sugar:~ $ echo "?ta" > r
rq@sugar:~ $ iconv -futf-8 -tascii r
iconv: illegal input sequence at position 0
rq@sugar:~ $ echo "ruta" > r
rq@sugar:~ $ iconv -futf-8 -tascii r
ruta


Reproduce code:
---------------
I wrote a small testcase script to demonstrate this issue. It's located at:
http://jazz.lma.lt/~rq/iconv.php
and source is at:
http://jazz.lma.lt/~rq/iconv.phps.

For example, check out these two links:
http://jazz.lma.lt/~rq/iconv.php?text=r%C3%BBta&charset=ascii&submit=
http://jazz.lma.lt/~rq/iconv.php?text=%C3%BBta&charset=ascii&submit=

The only difference in them is an "r" letter in the beginning of the "text" variable. And in case it exists in "text", no errors are reported.

Expected result:
----------------
In both cases, iconv() should have reported an error.

Actual result:
--------------
iconv() did not return an error in the first case, when there was an ASCII letter before any unconvertable strings.