ADDITIONAL SYSTEM INFORMATION :
Affects systems that use bsd m4 with autoconf configure always fails with an error such as this:

configure: error: unrecognized options: --disable-ccache
configure exiting with result code 1

A DESCRIPTION OF THE PROBLEM :
JDK-8240820 modified UTIL_DEFUN_NAMED and introduced a non-portable m4 regular expression [^\s*] in the following line:

` m4_pushdef([ARG_][]arg_name, m4_bpatsubst(m4_substr(arg, m4_incr(m4_incr(m4_bregexp(arg, [: ])))), [^\s*], []))`

m4 regular expressions syntax is the same as in gnu emacs [1]. `\s*` is not valid for emacs regular expressions. `\s` in emacs must be followed by a character that designates a particular syntax class [2] and `*` is not one of them [3].

On systems that use BSD m4 with autoconf the regular expression doesn’t work and causes configure to fail. I tried to find a regular expression that works for both BSD m4 and gnu m4 and they both don’t implement gnu emacs regular expressions fully. I came up with this that works for both: `[^[ ]*]`. The inner brackets contain a space and a tab character.

In addition to the above the following line was added to insert a space after the colon when a space was missing:

` m4_if(m4_bregexp(arg, [: ]), -1, m4_define([arg], m4_bpatsubst(arg, [:], [: ])))`

On both GNU m4 and BSD m4 this line always adds a space due to the m4_define in the else case being executed in regardless of the m4_if results. This can be reworked as follows which works correctly for both GNU m4 and BSD m4:

` m4_define([arg], m4_if(m4_bregexp(arg, [: ]), -1, m4_bpatsubst(arg, [:], [: ]), arg))`

Although it probably just would be better to not insert a space and match on `[:]` instead of `[: ]` in the subsequent m4_bregexp uses.

[1] https://www.gnu.org/software/m4/manual/m4-1.4.18/html_node/Patsubst.html
[2] https://www.gnu.org/software/emacs/manual/html_node/emacs/Regexp-Backslash.html#Regexp-Backslash
[3] https://www.gnu.org/software/emacs/manual/html_node/elisp/Syntax-Class-Table.html#Syntax-Class-Table


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