I tried doing a VPATH build referencing a source directory that I'd distclean'd but not maintainer-clean'd, which should simulate the case of a VPATH build from a tarball. I was quite surprised that it fell over:
... gcc -Wall -Wmissing-prototypes -Wpointer-arith -Wdeclaration-after-statement -Wendif-labels -Wmissing-format-attribute -Wformat-security -fno-strict-aliasing -fwrapv -g -O2 -I. -I/home/postgres/pgsql/src/bin/psql -I/home/postgres/pgsql/src/interfaces/libpq -I../../../src/include -I/home/postgres/pgsql/src/include -D_GNU_SOURCE -c -o sql_help.o sql_help.c gcc: sql_help.c: No such file or directory gcc: no input files make[3]: *** [sql_help.o] Error 1 make[3]: Leaving directory `/home/postgres/buildroot/src/bin/psql' gmake should be generating a path to sql_help.c, since that exists in the corresponding source directory, but it does not. I can reproduce this on RHEL6 with make-3.81-23, but not on Fedora 26 with make-4.2.1-2, and (curiously) also not on High Sierra with Apple's copy of make 3.81. I wonder how many other people see it. The attached patch seems to fix it, indicating that there's something about the rules relating sql_help.c and sql_help.h that is confusing make, such that turning sql_help.c into the primary target for the create_help rule removes the confusion. Comments? regards, tom lane
diff --git a/src/bin/psql/Makefile b/src/bin/psql/Makefile index c8eb2f9..4482097 100644 *** a/src/bin/psql/Makefile --- b/src/bin/psql/Makefile *************** psql: $(OBJS) | submake-libpq submake-li *** 35,49 **** help.o: sql_help.h ! sql_help.c: sql_help.h ; ! sql_help.h: create_help.pl $(wildcard $(REFDOCDIR)/*.sgml) $(PERL) $< $(REFDOCDIR) $* psqlscanslash.c: FLEXFLAGS = -Cfe -p -p psqlscanslash.c: FLEX_NO_BACKUP=yes psqlscanslash.c: FLEX_FIX_WARNING=yes ! distprep: sql_help.h psqlscanslash.c install: all installdirs $(INSTALL_PROGRAM) psql$(X) '$(DESTDIR)$(bindir)/psql$(X)' --- 35,49 ---- help.o: sql_help.h ! sql_help.h: sql_help.c ; ! sql_help.c: create_help.pl $(wildcard $(REFDOCDIR)/*.sgml) $(PERL) $< $(REFDOCDIR) $* psqlscanslash.c: FLEXFLAGS = -Cfe -p -p psqlscanslash.c: FLEX_NO_BACKUP=yes psqlscanslash.c: FLEX_FIX_WARNING=yes ! distprep: sql_help.c psqlscanslash.c install: all installdirs $(INSTALL_PROGRAM) psql$(X) '$(DESTDIR)$(bindir)/psql$(X)'