From 6c9a393f954805d49ab6c66957b46199ddd6e78e Mon Sep 17 00:00:00 2001 From: Paul Smith Date: Tue, 9 Jul 2002 06:35:56 +0000 Subject: Documentation and tests for order-only prerequisites. Add a new test suite for automatic variables. --- AUTHORS | 1 + ChangeLog | 20 +++++++++++++--- NEWS | 7 ++++++ commands.c | 2 +- doc/make.texi | 48 +++++++++++++++++++++++++++++++++++-- file.c | 19 +++++++++++++-- read.c | 11 +++++++-- tests/ChangeLog | 8 +++++++ tests/scripts/features/order_only | 47 ++++++++++++++++++++++++++++++------ tests/scripts/variables/automatic | 50 +++++++++++++++++++++++++++++++++++++++ 10 files changed, 196 insertions(+), 17 deletions(-) create mode 100644 tests/scripts/variables/automatic diff --git a/AUTHORS b/AUTHORS index e3acf48..88d61c3 100644 --- a/AUTHORS +++ b/AUTHORS @@ -47,6 +47,7 @@ Other contributors: Jim Kelton David Lubbren Tim Magill + Greg McGary Han-Wen Nienhuys Andreas Schwab Carl Staelin (Princeton University) diff --git a/ChangeLog b/ChangeLog index 65ba46f..97e88bc 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,11 +1,25 @@ +2002-07-09 Paul D. Smith + + * doc/make.texi (Prerequisite Types): Add a new section describing + order-only prerequisites. + + * read.c (uniquize_deps): If we have the same file as both a + normal and order-only prereq, get rid of the order-only prereq, + since the normal one supersedes it. + 2002-07-08 Paul D. Smith + * AUTHORS: Added Greg McGary to the AUTHORS file. + * NEWS: Blurbed order-only prerequisites. + * file.c (print_file): Show order-only deps properly when printing + the database. + * maintMakefile: Add "update" targets for wget'ing the latest versions of various external files. Taken from Makefile.maint in autoconf, etc. - * dosbuild.bat: Somehow we got _extra_ ^M's. Remove them. - Reported by Eli Zaretskii . + * dosbuild.bat: Somehow we got _double_ ^M's. Remove them. + Reported by Eli Zaretskii . 2002-07-07 Paul D. Smith @@ -22,7 +36,7 @@ * implicit.c (pattern_search): Some systems apparently run short of stack space, and using alloca() in this function caused an overrun. I modified it to use xmalloc() on the two variables - which seemed like they might get large. Bug #476. + which seemed like they might get large. Fixes Bug #476. * main.c (print_version): Update copyright notice to conform with GNU standards. diff --git a/NEWS b/NEWS index 0237ae4..4c73093 100644 --- a/NEWS +++ b/NEWS @@ -14,6 +14,13 @@ reports. Version +* 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 . + * A new function is defined: $(quote ...). 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. diff --git a/commands.c b/commands.c index 19a175e..f6baefc 100644 --- a/commands.c +++ b/commands.c @@ -124,7 +124,7 @@ set_file_variables (file) DEFINE_VARIABLE ("@", 1, at); DEFINE_VARIABLE ("%", 1, percent); - /* Compute the values for $^, $+, and $?. */ + /* Compute the values for $^, $+, $?, and $|. */ { unsigned int qmark_len, plus_len, bar_len; diff --git a/doc/make.texi b/doc/make.texi index 20fc1c8..6fac114 100644 --- a/doc/make.texi +++ b/doc/make.texi @@ -158,6 +158,7 @@ Writing Rules * Rule Example:: An example explained. * Rule Syntax:: General syntax explained. +* Prerequisite Types:: There are two types of prerequisites. * Wildcards:: Using wildcard characters such as `*'. * Directory Search:: Searching other directories for source files. * Phony Targets:: Using a target that is not a real file's name. @@ -1473,6 +1474,7 @@ the makefile (often with a target called @samp{all}). @menu * Rule Example:: An example explained. * Rule Syntax:: General syntax explained. +* Prerequisite Types:: There are two types of prerequisites. * Wildcards:: Using wildcard characters such as `*'. * Directory Search:: Searching other directories for source files. * Phony Targets:: Using a target that is not a real file's name. @@ -1524,7 +1526,7 @@ added to the prerequisites. @end itemize @end ifinfo -@node Rule Syntax, Wildcards, Rule Example, Rules +@node Rule Syntax, Prerequisite Types, Rule Example, Rules @section Rule Syntax @cindex rule syntax @@ -1593,7 +1595,49 @@ How to update is specified by @var{commands}. These are lines to be executed by the shell (normally @samp{sh}), but with some extra features (@pxref{Commands, ,Writing the Commands in Rules}). -@node Wildcards, Directory Search, Rule Syntax, Rules +@node Prerequisite Types, Wildcards, Rule Syntax, Rules +@comment node-name, next, previous, up +@section Types of Prerequisites +@cindex prerequisite types +@cindex types of prerequisites + +@cindex prerequisites, normal +@cindex normal prerequisites +@cindex prerequisites, order-only +@cindex order-only prerequisites +There are actually two different types of prerequisites understood by +GNU @code{make}: normal prerequisites such as described in the +previous section, and @dfn{order-only} prerequisites. A normal +prerequisite actually makes two statements: first, it imposes an order +of execution of build commands: any commands necessary to build any of +a target's prerequisites will be fully executed before any commands +necessary to build the target. Second, it imposes a dependency +relationship: if any prerequisite is newer than the target, then the +target is considered out-of-date and must be rebuilt. + +Normally, this is exactly what you want: if a target's prerequisite is +updated, then the target should also be updated. + +Occasionally, however, you have a situation where you want to impose a +specific ordering on the rules to be invoked @emph{without} forcing +the target to be updated if one of those rules is executed. In that +case, you want to define @dfn{order-only} prerequisites. Order-only +prerequisites can be specified by placing a pipe symbol (@code{|}) +in the prerequisites list: any prerequisites to the left of the pipe +symbol are normal; any prerequisites to the right are order-only: + +@example +@var{targets} : @var{normal-prerequisites} | @var{order-only-prerequisites} +@end example + +The normal prerequisites section may of course be empty. Also, you +may still declare multiple lines of prerequisites for the same target: +they are appended appropriately. Note that if you declare the same +file to be both a normal and an order-only prerequisite, the normal +prerequisite takes precedence (since they are a strict superset of the +behavior of an order-only prerequisite). + +@node Wildcards, Directory Search, Prerequisite Types, Rules @section Using Wildcard Characters in File Names @cindex wildcard @cindex file name with wildcards diff --git a/file.c b/file.c index 2602810..1e87443 100644 --- a/file.c +++ b/file.c @@ -680,15 +680,30 @@ static void print_file (f) struct file *f; { - register struct dep *d; + struct dep *d; + struct dep *ood = 0; putchar ('\n'); if (!f->is_target) puts (_("# Not a target:")); printf ("%s:%s", f->name, f->double_colon ? ":" : ""); + /* Print all normal dependencies; note any order-only deps. */ for (d = f->deps; d != 0; d = d->next) - printf (" %s", dep_name (d)); + if (! d->ignore_mtime) + printf (" %s", dep_name (d)); + else if (! ood) + ood = d; + + /* Print order-only deps, if we have any. */ + if (ood) + { + printf (" | %s", dep_name (ood)); + for (d = ood->next; d != 0; d = d->next) + if (d->ignore_mtime) + printf (" %s", dep_name (d)); + } + putchar ('\n'); if (f->precious) diff --git a/read.c b/read.c index 510266a..4b7c79c 100644 --- a/read.c +++ b/read.c @@ -1524,10 +1524,17 @@ uniquize_deps (chain) last = d; next = d->next; while (next != 0) - if (streq (dep_name (d), dep_name (next)) - && d->ignore_mtime == next->ignore_mtime) + if (streq (dep_name (d), dep_name (next))) { struct dep *n = next->next; + /* If ignore_mtimes are not equal, one of these is an order-only + prerequisite and one isn't. That means that we should remove + the one that isn't and keep the one that is. Ideally we'd + like to keep the normal one always but that's hard, and + probably not very important, so just remove the second one and + force the first one to be normal. */ + if (d->ignore_mtime != next->ignore_mtime) + d->ignore_mtime = 0; last->next = n; if (next->name != 0 && next->name != d->name) free (next->name); diff --git a/tests/ChangeLog b/tests/ChangeLog index aa5f78d..fec5186 100644 --- a/tests/ChangeLog +++ b/tests/ChangeLog @@ -1,3 +1,11 @@ +2002-07-09 Paul D. Smith + + * scripts/variables/automatic: Create a test for automatic variables. + +2002-07-08 Paul D. Smith + + * scripts/features/order_only: Test new order-only prerequisites. + 2002-07-07 Paul D. Smith * scripts/functions/eval: Test new function. diff --git a/tests/scripts/features/order_only b/tests/scripts/features/order_only index 81284c5..e324d68 100644 --- a/tests/scripts/features/order_only +++ b/tests/scripts/features/order_only @@ -10,7 +10,6 @@ open(MAKEFILE,"> $makefile"); print MAKEFILE <<'EOF'; foo: bar | baz @echo '$$^ = $^' - @echo '$$? = $?' @echo '$$| = $|' touch $@ @@ -26,7 +25,7 @@ close(MAKEFILE); # TEST #1 -- just the syntax &run_make_with_options($makefile, "", &get_logfile); -$answer = "touch bar\ntouch baz\n\$^ = bar\n\$? = bar\n\$| = baz\ntouch foo\n"; +$answer = "touch bar\ntouch baz\n\$^ = bar\n\$| = baz\ntouch foo\n"; &compare_output($answer,&get_logfile(1)); @@ -47,7 +46,6 @@ open(MAKEFILE,"> $makefile2"); print MAKEFILE <<'EOF'; foo: bar | baz @echo '$$^ = $^' - @echo '$$? = $?' @echo '$$| = $|' touch $@ @@ -61,19 +59,54 @@ EOF close(MAKEFILE); -# TEST #3 -- just the syntax +# TEST #3 -- Make sure the order-only prereq was promoted to normal. &run_make_with_options($makefile2, "", &get_logfile); -$answer = "touch bar\ntouch baz\n\$^ = bar baz\n\$? = bar baz\n\$| = baz\ntouch foo\n"; +$answer = "touch bar\ntouch baz\n\$^ = bar baz\n\$| = \ntouch foo\n"; &compare_output($answer,&get_logfile(1)); -# TEST #2 -- now we do it again: baz is PHONY but foo should _NOT_ be updated +# TEST #4 -- now we do it again &run_make_with_options($makefile2, "", &get_logfile); -$answer = "touch baz\$^ = bar baz\n\$? = baz\n\$| = baz\ntouch foo\n"; +$answer = "touch baz\n\$^ = bar baz\n\$| = \ntouch foo\n"; &compare_output($answer,&get_logfile(1)); unlink(qw(foo bar baz)); +# Test empty normal prereqs + +$makefile3 = &get_tmpfile; + +open(MAKEFILE,"> $makefile3"); + +print MAKEFILE <<'EOF'; +foo:| baz + @echo '$$^ = $^' + @echo '$$| = $|' + touch $@ + +.PHONY: baz + +baz: + touch $@ +EOF + +close(MAKEFILE); + +# TEST #5 -- make sure the parser was correct. + +&run_make_with_options($makefile3, "", &get_logfile); +$answer = "touch baz\n\$^ = \n\$| = baz\ntouch foo\n"; +&compare_output($answer,&get_logfile(1)); + + +# TEST #6 -- now we do it again: this time foo won't be built + +&run_make_with_options($makefile3, "", &get_logfile); +$answer = "touch baz\n"; +&compare_output($answer,&get_logfile(1)); + +unlink(qw(foo baz)); + 1; diff --git a/tests/scripts/variables/automatic b/tests/scripts/variables/automatic new file mode 100644 index 0000000..b80d478 --- /dev/null +++ b/tests/scripts/variables/automatic @@ -0,0 +1,50 @@ +# -*-perl-*- + +$description = "Test automatic variable setting."; + +$details = ""; + +use Cwd; + +$dir = cwd; +$dir =~ s,.*/([^/]+)$,../$1,; + +open(MAKEFILE, "> $makefile"); +print MAKEFILE "dir = $dir\n"; +print MAKEFILE <<'EOF'; +.SUFFIXES: +.SUFFIXES: .x .y .z +$(dir)/foo.x : baz.z $(dir)/bar.y baz.z + @echo '$$@ = $@, $$(@D) = $(@D), $$(@F) = $(@F)' + @echo '$$* = $*, $$(*D) = $(*D), $$(*F) = $(*F)' + @echo '$$< = $<, $$(