I was originally intending to preserve some of Jarmo Jaakkola's notes
on POSIX make from the PR 49085 changes... but really there's no point
wandering into details about $? and such when the big picture is
"almost everything in this manual works only in BSD make".
Maybe the exact details can be stuffed into a chapter of the mythical
make reference manual if that ever gets (re)written.
appeared in the PR 49085 changes, even though it's not actually
relevant there except tangentially. However, I've reworked most of
that for clarity and added some more.
Quite extensive rewrite of the Suff module. Some ripple effects into
Parse and Targ modules too.
Dependency searches in general were made to honor explicit rules so
implicit and explicit sources are no longer applied on targets that
do not invoke a transformation rule.
Archive member dependency search was rewritten. Explicit rules now
work properly and $(.TARGET) is set correctly. POSIX semantics for
lib(member.o) and .s1.a rules are supported.
.SUFFIXES list maintenance was rewritten so that scanning of existing
rules works when suffixes are added and that clearing the suffix list
removes single suffix rules too. Transformation rule nodes are now
mixed with regular nodes so they are available as regular targets too
if needed (especially after the known suffixes are cleared).
The .NULL target was documented in the manual page, especially to
warn against using it when a single suffix rule would work.
A deprecation warning was also added to the manual and make also
warns the user if it encounters .NULL.
Search for suffix rules no longer allows the explicit dependencies
to override the selected transformation rule. A check is made in
the search that the transformation that would be tried does not
already exist in the chain. This prevents getting stuck in an infinite
loop under specific circumstances. Local variables are now set
before node's children are expanded so dynamic sources work in
multi-stage transformations. Make_HandleUse() no longer expands
the added children for transformation nodes, preventing triple
expansion and allowing the Suff module to properly postpone their
expansion until proper values are set for the local variables.
Directory prefix is no longer removed from $(.PREFIX) if the target
is found via directory search.
The last rule defined is now used instead of the first one (POSIX
requirement) in case a rule is defined multiple times. Everything
defined in the first instance is undone, but things added "globally"
are honored. To implement this, each node tracks attribute bits
which have been set by special targets (global) instead of special
sources (local). They also track dependencies that were added by
a rule with commands (local) instead of rule with no commands (global).
New attribute, OP_FROM_SYS_MK is introduced. It is set on all targets
found in system makefiles so that they are not eligible to become
the main target. We cannot just set OP_NOTMAIN because it is one of
the attributes inherited from transformation and .USE rules and would
make any eligible target that uses a built-in inference rule ineligible.
The $(.IMPSRC) local variable now works like in gmake: it is set to
the first prerequisite for explicit rules. For implicit rules it
is still the implied source.
The manual page is improved regarding the fixed features. Test cases
for the fixed problems are added.
Other improvements in the Suff module include:
- better debug messages for transformation rule search (length of
the chain is now visualized by indentation)
- Suff structures are created, destroyed and moved around by a set
of maintenance functions so their reference counts are easier
to track (this also gets rid of a lot of code duplication)
- some unreasonably long functions were split into smaller ones
- many local variables had their names changed to describe their
purpose instead of their type
Don't exit from var.c:Var_Parse() before possible modifiers are handled
on D and F modified versions of local variables. Properly expand $(?D)
and $(?F) too.
Make line continuations in rule's commands POSIX compliant.
Fix the syntax error caused by lib(member) as the last target before
a dependency operator.
Document the line continuation change in the manual page. Also talk
more about the POSIX style local variables and their modifiers.
Add tests covering the fixed problems into d_posix.mk. The test is
a known failure at the moment because of PR 49086 and PR 49092.
[XXX: unconverted tests]
subjected to variable expansion before regexp parsing. This was already
documented if you read carefully enough, but more emphasis would have
helped me to figure out why I needed three or four backslashes where I
expected to need only two.
1. add -w flag to print Entering and Leaving directory name the the beginning
and the end of processing.
2. export MAKELEVEL=$((MAKELEVEL + 1)) only in the child environment.
3. when printing error messages, prefix them with the program name [$MAKELEVEL]
for $MAKELEVEL > 0
4. if $MAKEFLAGS consists only of letters assume it is a set of flags (as
allowed by posix), convert them to -f -l -a -g -s, so that they get parsed
properly.
With those fixes gmake -> bmake -> gmake -> bmake etc. works as expected.
Rather than apply it to the whole script, just the current command line
is affected. This allows a trick like ${.OODATE:M.NOMETA_CMP}
to cause command comparison to be supressed for one command only.
behavior in jobs vs non-jobs mode.
Move the comment about when shell is skipped to this discussion
from COMPATABILITY.
Remove the incorrect statement about default mode being somehow
neither jobs mode or compat mode (it is compat mode).
The default retains the traditional NetBSD behavior, but the knob
can be set so that FreeBSD can retain their expected behavior.
This is a compromise to be sure.
Add a debug flag -dV to override the above, so that regardless of
the knob setting, the raw value of a variable can be easily seen.
These capture all the interesting data - useful for debugging.
In such cases there is no need to replicate commands in the build log.
Rather than run the entire build .SILENT, allow meta mode to set that flag
per target iff a .meta file is created.
Normal behavior is retained for targets where no .meta file is created,
ensuring that no build data is lost.
