From 29180e5d78e545472b1665b8d415e6917a5bf333 Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sat, 1 Dec 2018 17:19:51 -0500 Subject: [PATCH] Eliminate parallel-make hazard in ecpg/preproc. Re-making ecpglib's typename.o is dangerous because another make thread could be doing that at the same time. While we've not heard field complaints traceable to this, it seems inevitable that it'd bite someone eventually. Instead, symlink typename.c into the preproc directory and recompile it there. That file is small enough that compiling it twice isn't much of a penalty. Furthermore, this way we get a .o file that's made without shlib CFLAGS, which seems cleaner. This requires adding more stuff to the module's -I list. The MSVC aspect of that is untested, but I'm sure the buildfarm will tell me if I got it wrong. Per a suggestion from Peter Eisentraut. Although this is theoretically a bug fix, the lack of field reports makes me feel we needn't back-patch. Discussion: https://postgr.es/m/31364.1543511708@sss.pgh.pa.us --- src/interfaces/ecpg/preproc/.gitignore | 2 +- src/interfaces/ecpg/preproc/Makefile | 15 ++++++++++----- src/tools/msvc/Mkvcbuild.pm | 1 + 3 files changed, 12 insertions(+), 6 deletions(-) diff --git a/src/interfaces/ecpg/preproc/.gitignore b/src/interfaces/ecpg/preproc/.gitignore index aacfb844bd..38ae2fe4d9 100644 --- a/src/interfaces/ecpg/preproc/.gitignore +++ b/src/interfaces/ecpg/preproc/.gitignore @@ -2,5 +2,5 @@ /preproc.c /preproc.h /pgc.c - +/typename.c /ecpg diff --git a/src/interfaces/ecpg/preproc/Makefile b/src/interfaces/ecpg/preproc/Makefile index 07721752c8..8ceadd112b 100644 --- a/src/interfaces/ecpg/preproc/Makefile +++ b/src/interfaces/ecpg/preproc/Makefile @@ -16,13 +16,16 @@ top_builddir = ../../../.. include $(top_builddir)/src/Makefile.global override CPPFLAGS := -I../include -I$(top_srcdir)/src/interfaces/ecpg/include \ - -I. -I$(srcdir) -DECPG_COMPILE \ - $(CPPFLAGS) + -I. -I$(srcdir) \ + -I$(top_srcdir)/src/interfaces/ecpg/ecpglib \ + -I$(libpq_srcdir) \ + -DECPG_COMPILE \ + $(CPPFLAGS) override CFLAGS += $(PTHREAD_CFLAGS) OBJS= preproc.o pgc.o type.o ecpg.o output.o parser.o \ - keywords.o c_keywords.o ecpg_keywords.o ../ecpglib/typename.o descriptor.o variable.o \ + keywords.o c_keywords.o ecpg_keywords.o typename.o descriptor.o variable.o \ $(WIN32RES) # Suppress parallel build to avoid a bug in GNU make 3.82 @@ -36,8 +39,9 @@ all: ecpg ecpg: $(OBJS) | submake-libpgport $(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_EX) $^ $(LIBS) $(PTHREAD_LIBS) -o $@$(X) -../ecpglib/typename.o: ../ecpglib/typename.c - $(MAKE) -C $(dir $@) $(notdir $@) +# We symlink typename.c from ecpglib and recompile it here +typename.c: % : $(top_srcdir)/src/interfaces/ecpg/ecpglib/% + rm -f $@ && $(LN_S) $< . # See notes in src/backend/parser/Makefile about the following two rules preproc.h: preproc.c @@ -64,6 +68,7 @@ uninstall: clean distclean: rm -f *.o ecpg$(X) + rm -f typename.c # `make distclean' must not remove preproc.y, preproc.c, preproc.h, or pgc.c # since we want to ship those files in the distribution for people with diff --git a/src/tools/msvc/Mkvcbuild.pm b/src/tools/msvc/Mkvcbuild.pm index b562044fa7..2921d193a1 100644 --- a/src/tools/msvc/Mkvcbuild.pm +++ b/src/tools/msvc/Mkvcbuild.pm @@ -291,6 +291,7 @@ sub mkvcbuild my $ecpg = $solution->AddProject('ecpg', 'exe', 'interfaces', 'src/interfaces/ecpg/preproc'); $ecpg->AddIncludeDir('src/interfaces/ecpg/include'); + $ecpg->AddIncludeDir('src/interfaces/ecpg/ecpglib'); $ecpg->AddIncludeDir('src/interfaces/libpq'); $ecpg->AddPrefixInclude('src/interfaces/ecpg/preproc'); $ecpg->AddFiles('src/interfaces/ecpg/preproc', 'pgc.l', 'preproc.y'); -- 2.40.0