Re: [ft] Question: linker errors when building freetype for iOS in Xcode

[Werner LEMBERG]

> Given it is `m4trace` that is producing the error message, I checked
> the installed version of `m4`:
> 
> GNU M4 1.4.6

According to the autoconf manual, this is OK, but 1.4.13 or newer
would be better.  I recommend installing a new version.

> Which tool is interpreting this `configure.ac`?

The `autoconf' script, which is a wrapper for `autom4te' (written in
Perl), which in turn is a wrapper around the `m4' preprocessor.

> Should this file also start with a shell invocation, as it does not?

No.  The git archive only contains `configure.raw', which gets
converted to `configure.ac' by FreeType's top-level `autogen.sh'
script.  This `configure.ac' is in turn a template file for the
`autoconf' program that expands m4 macros like AC_INIT together with
adding more code to create a valid shell script.

> Should everything in parentheses in `configure.ac` have been replaced
> during the autotools procedure?

No.  But everything starting with `AC_' should be replaced with valid
shell script code.  BTW, m4 arguments are normally enclosed in
brackets.

> Or is the format of the line in the error correct, and the tool that
> is interpreting it unfit for purpose?

I don't know. :-)

I still recommend to install the newest versions of the autotools (and
m4).  Doing so all necessary prerequisites are checked, which could
unveil problems not easily noticed otherwise.


    Werner