Changes since 3.79.1 are:
Version 3.80
* A new feature exists: order-only prerequisites. These prerequisites
affect the order in which targets are built, but they do not impact
the rebuild/no-rebuild decision of their dependents. That is to say,
they allow you to require target B be built before target A, without
requiring that target A will always be rebuilt if target B is updated.
Patch for this feature provided by Greg McGary <greg@mcgary.org>.
* For compatibility with SysV make, GNU make now supports the peculiar
syntax $$@, $$(@D), and $$(@F) in the prerequisites list of a rule.
This syntax is only valid within explicit and static pattern rules: it
cannot be used in implicit (suffix or pattern) rules. Edouard G. Parmelan
<egp@free.fr> provided a patch implementing this feature; however, I
decided to implement it in a different way.
* The argument to the "ifdef" conditional is now expanded before it's
tested, so it can be a constructed variable name.
Similarly, the arguments to "export" (when not used in a variable
definition context) and "unexport" are also now expanded.
* A new function is defined: $(value ...). The argument to this
function is the _name_ of a variable. The result of the function is
the value of the variable, without having been expanded.
* A new function is defined: $(eval ...). The arguments to this
function should expand to makefile commands, which will then be
evaluated as if they had appeared in the makefile. In combination
with define/endef multiline variable definitions this is an extremely
powerful capability. The $(value ...) function is also sometimes
useful here.
* A new built-in variable is defined, $(MAKEFILE_LIST). It contains a
list of each makefile GNU make has read, or started to read, in the
order in which they were encountered. So, the last filename in the
list when a makefile is just being read (before any includes) is the
name of the current makefile.
* A new built-in variable is defined: $(.VARIABLES). When it is
expanded it returns a complete list of variable names defined by all
makefiles at that moment.
* A new command-line option is defined, -B or --always-make. If
specified GNU make will consider all targets out-of-date even if they
would otherwise not be.
* The arguments to $(call ...) functions were being stored in $1, $2,
etc. as recursive variables, even though they are fully expanded
before assignment. This means that escaped dollar signs ($$ etc.)
were not behaving properly. Now the arguments are stored as simple
variables. This may mean that if you added extra escaping to your
$(call ...) function arguments you will need to undo it now.
* The variable invoked by $(call ...) can now be recursive: unlike other
variables it can reference itself and this will not produce an error
when it is used as the first argument to $(call ...) (but only then).
* New pseudo-target .LOW_RESOLUTION_TIME, superseding the configure
option --disable-nsec-timestamps. You might need this if your build
process depends on tools like "cp -p" preserving time stamps, since
"cp -p" (right now) doesn't preserve the subsecond portion of a time
stamp.
* Updated translations for French, Galician, German, Japanese, Korean,
and Russian. New translations for Croatian, Danish, Hebrew, and
Turkish.
* Updated internationalization support to Gettext 0.11.5.
GNU make now uses Gettext's "external" feature, and does not include
any internationalization code itself. Configure will search your
system for an existing implementation of GNU Gettext (only GNU Gettext
is acceptable) and use it if it exists. If not, NLS will be disabled.
See ABOUT-NLS for more information.
* Updated to autoconf 2.54 and automake 1.7. Users should not be impacted.
