cleanups.
If we find a make error (invalid makefile syntax or something like that)
write back any tokens we have before we exit.
If we have waiting jobs (using -j + -l) set an alarm before we sleep on
the read() system call, so we can wake up to check the load and start
waiting jobs, if there are long-running jobs we would otherwise be
waiting for. Suggested by Grant Taylor.
Taylor. There are two forms of this: first, it was possible to lose
tokens when using -j and -l at the same time, because waiting jobs were
not checked when determining whether any jobs were outstanding. Second,
if you had an exported recursive variable that contained a $(shell ...)
function there is a possibility to lose tokens, since a token was taken
but the child list was not updated until after the shell function was
complete.
To resolve this I introduced a new variable that counted the number of
tokens we have obtained, rather than checking whether there were any
children on the list. I also added some sanity checks to make sure we
weren't writing back too many or not enough tokens. And, the master
make will drain the token pipe before exiting and compare the count of
tokens at the end to what was written there at the beginning.
Also:
* Ensure a bug in the environment (missing "=") doesn't cause make to core.
* Rename the .DEFAULT_TARGET variable to .DEFAULT_GOAL, to match the
terminology in the documentation and other variables like MAKECMDGOALS.
* Add documentation of the .DEFAULT_GOAL special variable.
Still need to document the secondary expansion stuff...
I did this by adding intelligence into the algorithm such that the
second expansion was only actually performed when the prerequisite list
contained at least one "$", so we knew it is actually needed.
Without this we were using up a LOT more memory, since every single
target (even ones never used by make) had their file variables
initialized. This also used a lot more CPU, since we needed to create
and populate a new variable hash table for every target.
There is one issue remaining with this feature: it leaks memory. In
pattern_search() we now initialize the file variables for every pattern
target, which allocates a hash table, etc. However, sometimes we
recursively invoke pattern_search() (for intermediate files) with an
automatic variable (alloca() I believe) as the file. When that function
returns, obviously, the file variable hash memory is lost.
* New function: $(info ...)
* Disallow $(eval ...) to create prereq relationships inside command scripts
(caused core dumps)
* Try to allow more tests to succeed in Windows/DOS by sanitizing CRLF and \
* Various bug fixes and code cleanups (see the ChangeLog entry)
Fix references to MINGW #define constants.
Remove WINDOWS32 ifdef from sub_proc.h.
Only add variables to the command line for recursion once.
New features in run_make_test: #PWD# and #MAKEPATH# replacements.
Test the multi-variable fix in the recursion regression test.
POSIX requires that the value of SHELL in the makefile NOT be exported
to sub-commands. Instead, the value in the environment when make was
invoked should be passed to the environment of sub-commands. Note that
make still uses SHELL to _run_ sub-commands; it just doesn't change the
value of the SHELL variable in the environment of sub-commands.
As an extension to POSIX, if the makefile explicitly exports SHELL then
GNU make _will_ use it in the environment of sub-commands.
reported by Markus Mauhart <qwe123@chello.at>. One was a simple typo; to
fix the other we call patsubst_expand() for all instances of variable
substitution, even when there is no '%'. We used to call subst_expand()
with a special flag set in the latter case, but it didn't work properly
in all situations. Easier to just use patsubst_expand() since that's
what it is.
