10 files changed, 59 insertions, 52 deletions
diff --git a/src/Makefile.shlib b/src/Makefile.shlib
index f50b0398c90..2ba92ce7121 100644
--- a/src/Makefile.shlib
+++ b/src/Makefile.shlib
@@ -338,13 +338,9 @@ else # PORTNAME == aix
 
 # AIX case
 
-# There is no correct way to write a rule that generates two files.
-# Rules with two targets don't have that meaning, they are merely
-# shorthand for two otherwise separate rules.  To be safe for parallel
-# make, we must chain the dependencies like this.  The semicolon is
-# important, otherwise make will choose some built-in rule.
-
-$(stlib): $(shlib) ;
+# See notes in src/backend/parser/Makefile about the following two rules
+$(stlib): $(shlib)
+	touch $@
 
 $(shlib): $(OBJS) | $(SHLIB_PREREQS)
 	rm -f $(stlib)
@@ -375,13 +371,9 @@ else
 
 # Win32 case
 
-# There is no correct way to write a rule that generates two files.
-# Rules with two targets don't have that meaning, they are merely
-# shorthand for two otherwise separate rules.  To be safe for parallel
-# make, we must chain the dependencies like this.  The semicolon is
-# important, otherwise make will choose some built-in rule.
-
-$(stlib): $(shlib) ;
+# See notes in src/backend/parser/Makefile about the following two rules
+$(stlib): $(shlib)
+	touch $@
 
 # XXX A backend that loads a module linked with libgcc_s_dw2-1.dll will exit
 # uncleanly, hence -static-libgcc.  (Last verified with MinGW-w64 compilers
diff --git a/src/backend/Makefile b/src/backend/Makefile
index 3b08defe2bc..e124d1a75c0 100644
--- a/src/backend/Makefile
+++ b/src/backend/Makefile
@@ -69,13 +69,10 @@ ifeq ($(PORTNAME), cygwin)
 postgres: $(OBJS)
 	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_EX) $(export_dynamic) -Wl,--stack,$(WIN32_STACK_RLIMIT) -Wl,--export-all-symbols -Wl,--out-implib=libpostgres.a $(call expand_subsys,$^) $(LIBS) -o $@
 
-# There is no correct way to write a rule that generates two files.
-# Rules with two targets don't have that meaning, they are merely
-# shorthand for two otherwise separate rules.  To be safe for parallel
-# make, we must chain the dependencies like this.  The semicolon is
-# important, otherwise make will choose some built-in rule.
-
-libpostgres.a: postgres ;
+# libpostgres.a is actually built in the preceding rule, but we need this to
+# ensure it's newer than postgres; see notes in src/backend/parser/Makefile
+libpostgres.a: postgres
+	touch $@
 
 endif # cygwin
 
@@ -85,7 +82,10 @@ LIBS += -lsecur32
 postgres: $(OBJS) $(WIN32RES)
 	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_EX) -Wl,--stack=$(WIN32_STACK_RLIMIT) -Wl,--export-all-symbols -Wl,--out-implib=libpostgres.a $(call expand_subsys,$(OBJS)) $(WIN32RES) $(LIBS) -o $@$(X)
 
-libpostgres.a: postgres ;
+# libpostgres.a is actually built in the preceding rule, but we need this to
+# ensure it's newer than postgres; see notes in src/backend/parser/Makefile
+libpostgres.a: postgres
+	touch $@
 
 endif # win32
 
@@ -129,12 +129,18 @@ postgres.o: $(OBJS)
 # The following targets are specified in make commands that appear in
 # the make files in our subdirectories. Note that it's important we
 # match the dependencies shown in the subdirectory makefiles!
+# Also, in cases where a subdirectory makefile generates two files in
+# what's really one step, such as bison producing both gram.h and gram.c,
+# we must request making the one that is shown as the secondary (dependent)
+# output, else the timestamp on it might be wrong.  By project convention,
+# the .h file is the dependent one for bison output, so we need only request
+# that; but in other cases, request both for safety.
 
 parser/gram.h: parser/gram.y
 	$(MAKE) -C parser gram.h
 
 storage/lmgr/lwlocknames.h: storage/lmgr/generate-lwlocknames.pl storage/lmgr/lwlocknames.txt
-	$(MAKE) -C storage/lmgr lwlocknames.h
+	$(MAKE) -C storage/lmgr lwlocknames.h lwlocknames.c
 
 utils/errcodes.h: utils/generate-errcodes.pl utils/errcodes.txt
 	$(MAKE) -C utils errcodes.h
@@ -210,7 +216,7 @@ distprep:
 	$(MAKE) -C bootstrap	bootparse.c bootscanner.c
 	$(MAKE) -C catalog	schemapg.h postgres.bki postgres.description postgres.shdescription
 	$(MAKE) -C replication	repl_gram.c repl_scanner.c syncrep_gram.c syncrep_scanner.c
-	$(MAKE) -C storage/lmgr	lwlocknames.h
+	$(MAKE) -C storage/lmgr	lwlocknames.h lwlocknames.c
 	$(MAKE) -C utils	fmgrtab.c fmgroids.h errcodes.h
 	$(MAKE) -C utils/misc	guc-file.c
 	$(MAKE) -C utils/sort	qsort_tuple.c
diff --git a/src/backend/catalog/Makefile b/src/backend/catalog/Makefile
index 1ce76100497..4229c4fe000 100644
--- a/src/backend/catalog/Makefile
+++ b/src/backend/catalog/Makefile
@@ -21,7 +21,7 @@ BKIFILES = postgres.bki postgres.description postgres.shdescription
 
 include $(top_srcdir)/src/backend/common.mk
 
-all: $(BKIFILES) schemapg.h
+all: $(BKIFILES) schemapg.h postgres.description postgres.shdescription
 
 # Note: there are some undocumented dependencies on the ordering in which
 # the catalog header files are assembled into postgres.bki.  In particular,
@@ -51,12 +51,15 @@ catalogdir = $(top_srcdir)/src/backend/catalog
 # locations of headers that genbki.pl needs to read
 pg_includes = -I$(top_srcdir)/src/include/catalog -I$(top_builddir)/src/include/catalog
 
-# see explanation in ../parser/Makefile
-postgres.description: postgres.bki ;
+# see notes in src/backend/parser/Makefile about multiple output files
+postgres.description: postgres.bki
+	touch $@
 
-postgres.shdescription: postgres.bki ;
+postgres.shdescription: postgres.bki
+	touch $@
 
-schemapg.h: postgres.bki ;
+schemapg.h: postgres.bki
+	touch $@
 
 # Technically, this should depend on Makefile.global, but then
 # postgres.bki would need to be rebuilt after every configure run,
diff --git a/src/backend/parser/Makefile b/src/backend/parser/Makefile
index fdd8485cec5..161251a2f91 100644
--- a/src/backend/parser/Makefile
+++ b/src/backend/parser/Makefile
@@ -28,12 +28,17 @@ endif
 
 # There is no correct way to write a rule that generates two files.
 # Rules with two targets don't have that meaning, they are merely
-# shorthand for two otherwise separate rules.  To be safe for parallel
-# make, we must chain the dependencies like this.  The semicolon is
-# important, otherwise make will choose the built-in rule for
-# gram.y=>gram.c.
-
-gram.h: gram.c ;
+# shorthand for two otherwise separate rules.  If we have an action
+# that in fact generates two or more files, we must choose one of them
+# as primary and show it as the action's output, then make all of the
+# other output files dependent on the primary, like this.  Furthermore,
+# the "touch" action is essential, because it ensures that gram.h is
+# marked as newer than (or at least no older than) gram.c.  Without that,
+# make is likely to try to rebuild gram.h in subsequent runs, which causes
+# failures in VPATH builds from tarballs.
+
+gram.h: gram.c
+	touch $@
 
 gram.c: BISONFLAGS += -d
 gram.c: BISON_CHECK_CMD = $(PERL) $(srcdir)/check_keywords.pl $< $(top_srcdir)/src/include/parser/kwlist.h
diff --git a/src/backend/storage/lmgr/Makefile b/src/backend/storage/lmgr/Makefile
index cd6ec73f08f..d081209e8d7 100644
--- a/src/backend/storage/lmgr/Makefile
+++ b/src/backend/storage/lmgr/Makefile
@@ -25,8 +25,9 @@ s_lock_test: s_lock.c $(top_builddir)/src/port/libpgport.a
 	$(CC) $(CPPFLAGS) $(CFLAGS) -DS_LOCK_TEST=1 $(srcdir)/s_lock.c \
 		$(TASPATH) -L $(top_builddir)/src/port -lpgport -o s_lock_test
 
-# see explanation in ../../parser/Makefile
-lwlocknames.c: lwlocknames.h ;
+# see notes in src/backend/parser/Makefile
+lwlocknames.c: lwlocknames.h
+	touch $@
 
 lwlocknames.h: $(top_srcdir)/src/backend/storage/lmgr/lwlocknames.txt generate-lwlocknames.pl
 	$(PERL) $(srcdir)/generate-lwlocknames.pl $<
diff --git a/src/backend/utils/Makefile b/src/backend/utils/Makefile
index 83745337180..7540f10541f 100644
--- a/src/backend/utils/Makefile
+++ b/src/backend/utils/Makefile
@@ -20,8 +20,9 @@ all: errcodes.h fmgroids.h probes.h
 
 $(SUBDIRS:%=%-recursive): fmgroids.h
 
-# see explanation in ../parser/Makefile
-fmgroids.h: fmgrtab.c ;
+# see notes in src/backend/parser/Makefile
+fmgroids.h: fmgrtab.c
+	touch $@
 
 fmgrtab.c: Gen_fmgrtab.pl $(catalogdir)/Catalog.pm $(top_srcdir)/src/include/catalog/pg_proc.h
 	$(PERL) -I $(catalogdir) $< $(top_srcdir)/src/include/catalog/pg_proc.h
diff --git a/src/bin/psql/Makefile b/src/bin/psql/Makefile
index 4295154cae6..9199c3eaff1 100644
--- a/src/bin/psql/Makefile
+++ b/src/bin/psql/Makefile
@@ -35,7 +35,10 @@ psql: $(OBJS) | submake-libpq submake-libpgport submake-libpgfeutils
 
 help.o: sql_help.h
 
-sql_help.c: sql_help.h ;
+# See notes in src/backend/parser/Makefile about the following two rules
+sql_help.c: sql_help.h
+	touch $@
+
 sql_help.h: create_help.pl $(wildcard $(REFDOCDIR)/*.sgml)
 	$(PERL) $< $(REFDOCDIR) $*
 
@@ -47,7 +50,7 @@ ifeq ($(GCC),yes)
 psqlscanslash.o: CFLAGS += -Wno-error
 endif
 
-distprep: sql_help.h psqlscanslash.c
+distprep: sql_help.h sql_help.c psqlscanslash.c
 
 install: all installdirs
 	$(INSTALL_PROGRAM) psql$(X) '$(DESTDIR)$(bindir)/psql$(X)'
diff --git a/src/interfaces/ecpg/preproc/Makefile b/src/interfaces/ecpg/preproc/Makefile
index 30db5a049af..5ef30a9cae7 100644
--- a/src/interfaces/ecpg/preproc/Makefile
+++ b/src/interfaces/ecpg/preproc/Makefile
@@ -44,7 +44,10 @@ ecpg: $(OBJS) | submake-libpgport
 ../ecpglib/typename.o: ../ecpglib/typename.c
 	$(MAKE) -C $(dir $@) $(notdir $@)
 
-preproc.h: preproc.c ;
+# See notes in src/backend/parser/Makefile about the following two rules
+preproc.h: preproc.c
+	touch $@
+
 preproc.c: BISONFLAGS += -d
 
 preproc.y: ../../../backend/parser/gram.y parse.pl ecpg.addons ecpg.header ecpg.tokens ecpg.trailer ecpg.type
diff --git a/src/pl/plpgsql/src/Makefile b/src/pl/plpgsql/src/Makefile
index e073b2abd0a..5fb5025a6ab 100644
--- a/src/pl/plpgsql/src/Makefile
+++ b/src/pl/plpgsql/src/Makefile
@@ -58,7 +58,9 @@ uninstall-headers:
 pl_gram.o pl_handler.o pl_comp.o pl_exec.o pl_funcs.o pl_scanner.o: plpgsql.h pl_gram.h plerrcodes.h
 
 # See notes in src/backend/parser/Makefile about the following two rules
-pl_gram.h: pl_gram.c ;
+pl_gram.h: pl_gram.c
+	touch $@
+
 pl_gram.c: BISONFLAGS += -d
 
 # generate plerrcodes.h from src/backend/utils/errcodes.txt
diff --git a/src/test/isolation/Makefile b/src/test/isolation/Makefile
index 3d272d5b592..daf7600d842 100644
--- a/src/test/isolation/Makefile
+++ b/src/test/isolation/Makefile
@@ -29,15 +29,6 @@ isolationtester$(X): $(OBJS) | submake-libpq submake-libpgport
 
 distprep: specparse.c specscanner.c
 
-# There is no correct way to write a rule that generates two files.
-# Rules with two targets don't have that meaning, they are merely
-# shorthand for two otherwise separate rules.  To be safe for parallel
-# make, we must chain the dependencies like this.  The semicolon is
-# important, otherwise make will choose the built-in rule for
-# gram.y=>gram.c.
-
-specparse.h: specparse.c ;
-
 # specscanner is compiled as part of specparse
 specparse.o: specscanner.c