Re: [Mingw-msys] Re: MinGW libtool DLL failure

[Robert Boehne]

All,

The max_cmd_len variable is used to determine how long a command
can be executed.  When Libtool generates a link command that is
longer than this, it breaks the command into successive "ld -r"
invocations that are just short enough to be executed.  There are
other parts of the commands that aren't included when testing, so
the max_cmd_len variable can't be set to the actual limit, but
must be smaller.  Also, finding the actual limit would take much
longer so we set max_cmd_len to something safe.
  It is true that the checking takes some time, ~three seconds on
a newer Sun workstation (with large limit), but it isn't clear
to me why it would take even longer under MinGW.
  It is reasonable to set this to a hard limit if the test takes
a very long time, but the value to use is the same one that
Libtool's configury will calculate.  The problem with GTK+ is
that they archive two (or more) object files with the same name,
so successive ar commands replace the previous one with the
new one.  If a package needs the command line broken up, setting
this value to the maximum possible will speed up compilation
drastically, IMHO an important issue.

my $0.02

Robert

-- 
Robert Boehne             Software Engineer
Ricardo Software   Chicago Technical Center
TEL: (630)789-0003 x. 238
FAX: (630)789-0127
email:  rboehne AT ricardo-us DOT com