[12] RFR: 8214777: Avoid some GCC 8.X strncpy() errors in HotSpot

[Simon Tooke]

This small patch fixes some simple warnings in Hotspot code, found by
GCC 8.1

Essentially, any code sequence of the pattern

    int l = strlen(somestring)
    char* buffer = malloc(l + 1)
    strncpy(buffer, somestring, l)
    buffer[l] = 0

is replaced by

    int len = strlen(somestring)
    char* buffer = malloc(len + 1)
    strncpy(buffer, somestring, len + 1)

For xmlstream.cpp, this is actually a small inefficiency, as the null
byte is immediately overwritten; but it makes GCC happy.


Bug: https://bugs.openjdk.java.net/browse/JDK-8214777
Webrev:
http://cr.openjdk.java.net/~sgehwolf/webrevs/stooke/JDK-8214777/02/webrev/