Ensure link commands list *.o files before LDFLAGS.

It's important for link commands to list *.o input files before -l
switches for libraries, as library code may not get pulled into the link
unless referenced by an earlier command-line entry.  This is certainly
necessary for static libraries (.a style).  Apparently on some platforms
it is also necessary for shared libraries, as reported by Donald Dong.

We often put -l switches for within-tree libraries into LDFLAGS, meaning
that link commands that list *.o files after LDFLAGS are hazardous.
Most of our link commands got this right, but a few did not.  In
particular, places that relied on gmake's default implicit link rule
failed, because that puts LDFLAGS first.  Fix that by overriding the
built-in rule with our own.  The implicit link rules in
src/makefiles/Makefile.* for single-.o-file shared libraries mostly
got this wrong too, so fix them.  I also changed the link rules for the
backend and a couple of other places for consistency, even though they
are not (currently) at risk because they aren't adding any -l switches
to LDFLAGS.

Arguably, the real problem here is that we're abusing LDFLAGS by
putting -l switches in it and we should stop doing that.  But changing
that would be quite invasive, so I'm not eager to do so.

Perhaps this is a candidate for back-patching, but so far it seems
that problems can only be exhibited in test code we don't normally
build, and at least some of the problems are new in HEAD anyway.
So I'll refrain for now.

Donald Dong and Tom Lane

Discussion: https://postgr.es/m/CAKABAquXn-BF-vBeRZxhzvPyfMqgGuc74p8BmQZyCFDpyROBJQ@mail.gmail.com

14 files changed, 26 insertions, 22 deletions

diff --git a/src/Makefile.global.in b/src/Makefile.global.in
index 4b6bab37dc9..758ea4357a7 100644
--- a/src/Makefile.global.in
+++ b/src/Makefile.global.in
@@ -742,6 +742,13 @@ endif
 # tracking (see below) is used.
 %: %.c
 
+# Replace gmake's default rule for linking a single .o file to produce an
+# executable.  The main point here is to put LDFLAGS after the .o file,
+# since we put -l switches into LDFLAGS and those are order-sensitive.
+# In addition, include CFLAGS and LDFLAGS_EX per project conventions.
+%: %.o
+	$(CC) $(CFLAGS) $< $(LDFLAGS) $(LDFLAGS_EX) $(LIBS) -o $@$(X)
+
 ifndef PGXS
 
 # Remake Makefile.global from Makefile.global.in if the latter
diff --git a/src/backend/Makefile b/src/backend/Makefile
index e05f55cad49..478a96db9bc 100644
--- a/src/backend/Makefile
+++ b/src/backend/Makefile
@@ -60,7 +60,7 @@ ifneq ($(PORTNAME), win32)
 ifneq ($(PORTNAME), aix)
 
 postgres: $(OBJS)
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_EX) $(export_dynamic) $(call expand_subsys,$^) $(LIBS) -o $@
+	$(CC) $(CFLAGS) $(call expand_subsys,$^) $(LDFLAGS) $(LDFLAGS_EX) $(export_dynamic) $(LIBS) -o $@
 
 endif
 endif
@@ -69,7 +69,7 @@ endif
 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 $@
+	$(CC) $(CFLAGS) $(call expand_subsys,$^) $(LDFLAGS) $(LDFLAGS_EX) $(export_dynamic) -Wl,--stack,$(WIN32_STACK_RLIMIT) -Wl,--export-all-symbols -Wl,--out-implib=libpostgres.a $(LIBS) -o $@
 
 # 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
@@ -82,7 +82,7 @@ ifeq ($(PORTNAME), win32)
 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)
+	$(CC) $(CFLAGS) $(call expand_subsys,$(OBJS)) $(WIN32RES) $(LDFLAGS) $(LDFLAGS_EX) -Wl,--stack=$(WIN32_STACK_RLIMIT) -Wl,--export-all-symbols -Wl,--out-implib=libpostgres.a $(LIBS) -o $@$(X)
 
 # 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
@@ -94,7 +94,7 @@ endif # win32
 ifeq ($(PORTNAME), aix)
 
 postgres: $(POSTGRES_IMP)
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_EX) $(call expand_subsys,$(OBJS)) -Wl,-bE:$(top_builddir)/src/backend/$(POSTGRES_IMP) $(LIBS) -Wl,-brtllib -o $@
+	$(CC) $(CFLAGS) $(call expand_subsys,$(OBJS)) $(LDFLAGS) $(LDFLAGS_EX) -Wl,-bE:$(top_builddir)/src/backend/$(POSTGRES_IMP) $(LIBS) -Wl,-brtllib -o $@
 
 $(POSTGRES_IMP): $(OBJS)
 	$(LD) $(LDREL) $(LDOUT) SUBSYS.o $(call expand_subsys,$^)
@@ -117,7 +117,7 @@ $(top_builddir)/src/port/libpgport_srv.a: | submake-libpgport
 # The postgres.o target is needed by the rule in Makefile.global that
 # creates the exports file when MAKE_EXPORTS = true.
 postgres.o: $(OBJS)
-	$(CC) $(LDREL) $(LDFLAGS) $(LDFLAGS_EX) $(call expand_subsys,$^) $(LIBS) -o $@
+	$(CC) $(LDREL) $(call expand_subsys,$^) $(LDFLAGS) $(LDFLAGS_EX) $(LIBS) -o $@
 
 
 # The following targets are specified in make commands that appear in
@@ -319,4 +319,4 @@ maintainer-clean: distclean
 # are up to date.  It saves the time of doing all the submakes.
 .PHONY: quick
 quick: $(OBJS)
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_EX) $(export_dynamic) $(call expand_subsys,$^) $(LIBS) -o postgres
+	$(CC) $(CFLAGS) $(call expand_subsys,$^) $(LDFLAGS) $(LDFLAGS_EX) $(export_dynamic) $(LIBS) -o postgres
diff --git a/src/interfaces/ecpg/preproc/Makefile b/src/interfaces/ecpg/preproc/Makefile
index 911d03dbd14..69ddd8e9f71 100644
--- a/src/interfaces/ecpg/preproc/Makefile
+++ b/src/interfaces/ecpg/preproc/Makefile
@@ -37,7 +37,7 @@ endif
 all: ecpg
 
 ecpg: $(OBJS) | submake-libpgport
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_EX) $^ $(LIBS) $(PTHREAD_LIBS) -o $@$(X)
+	$(CC) $(CFLAGS) $^ $(LDFLAGS) $(LDFLAGS_EX) $(LIBS) $(PTHREAD_LIBS) -o $@$(X)
 
 # We symlink typename.c from ecpglib and recompile it here
 typename.c: % : $(top_srcdir)/src/interfaces/ecpg/ecpglib/%
diff --git a/src/interfaces/ecpg/test/Makefile b/src/interfaces/ecpg/test/Makefile
index c761a4dcb0d..be53b7b94dc 100644
--- a/src/interfaces/ecpg/test/Makefile
+++ b/src/interfaces/ecpg/test/Makefile
@@ -49,7 +49,7 @@ clean distclean maintainer-clean:
 all: pg_regress$(X)
 
 pg_regress$(X): pg_regress_ecpg.o $(WIN32RES) $(top_builddir)/src/test/regress/pg_regress.o
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_EX) $^ $(LIBS) -o $@
+	$(CC) $(CFLAGS) $^ $(LDFLAGS) $(LDFLAGS_EX) $(LIBS) -o $@
 
 $(top_builddir)/src/test/regress/pg_regress.o:
 	$(MAKE) -C $(dir $@) $(notdir $@)
diff --git a/src/interfaces/ecpg/test/Makefile.regress b/src/interfaces/ecpg/test/Makefile.regress
index 4da1bb8a036..b0647cd2c5f 100644
--- a/src/interfaces/ecpg/test/Makefile.regress
+++ b/src/interfaces/ecpg/test/Makefile.regress
@@ -21,9 +21,6 @@ ECPG_TEST_DEPENDENCIES = ../../preproc/ecpg$(X) \
 	$(srcdir)/../../include/sqltypes.h \
 	$(srcdir)/../../include/sql3types.h
 
-%: %.o
-	$(CC) $(CFLAGS) $< $(LDFLAGS) $(LDFLAGS_EX) $(LIBS) -o $@
-
 # Caution: this build rule is overridden in some child Makefiles
 # where it's necessary to use nondefault switches to ecpg;
 # make sure those rules match except for the extra switches.
diff --git a/src/makefiles/Makefile.aix b/src/makefiles/Makefile.aix
index e5ad89d1470..0f6c0289384 100644
--- a/src/makefiles/Makefile.aix
+++ b/src/makefiles/Makefile.aix
@@ -40,4 +40,4 @@ MKLDEXPORT=$(top_srcdir)/$(MKLDEXPORT_DIR)/mkldexport.sh
 
 # Rule for building a shared library from a single .o file
 %$(DLSUFFIX): %.o %.exp
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_SL) -o $@ $*.o -Wl,-bE:$*.exp $(BE_DLLLIBS)
+	$(CC) $(CFLAGS) $*.o $(LDFLAGS) $(LDFLAGS_SL) -o $@ -Wl,-bE:$*.exp $(BE_DLLLIBS)
diff --git a/src/makefiles/Makefile.darwin b/src/makefiles/Makefile.darwin
index 7a8ba3e5274..e2b1d44959f 100644
--- a/src/makefiles/Makefile.darwin
+++ b/src/makefiles/Makefile.darwin
@@ -10,4 +10,4 @@ endif
 
 # Rule for building a shared library from a single .o file
 %.so: %.o
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_SL) -bundle $(BE_DLLLIBS) -o $@ $<
+	$(CC) $(CFLAGS) $< $(LDFLAGS) $(LDFLAGS_SL) -bundle $(BE_DLLLIBS) -o $@
diff --git a/src/makefiles/Makefile.freebsd b/src/makefiles/Makefile.freebsd
index 5a98e5a2b0b..ce03c8dcd26 100644
--- a/src/makefiles/Makefile.freebsd
+++ b/src/makefiles/Makefile.freebsd
@@ -13,7 +13,7 @@ CFLAGS_SL = -fPIC -DPIC
 # Rule for building a shared library from a single .o file
 %.so: %.o
 ifdef ELF_SYSTEM
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@ $<
+	$(CC) $(CFLAGS) $< $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@
 else
 	$(LD) $(LDREL) $(LDOUT) $<.obj -x $<
 	@echo building shared object $@
diff --git a/src/makefiles/Makefile.hpux b/src/makefiles/Makefile.hpux
index 97bd0ba6d9e..30dd3eb77e6 100644
--- a/src/makefiles/Makefile.hpux
+++ b/src/makefiles/Makefile.hpux
@@ -40,13 +40,13 @@ endif
 %$(DLSUFFIX): %.o
 ifeq ($(GCC), yes)
   ifeq ($(with_gnu_ld), yes)
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@ $< `$(CC) $(LDFLAGS) -print-libgcc-file-name`
+	$(CC) $(CFLAGS) $< $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@ `$(CC) $(LDFLAGS) -print-libgcc-file-name`
   else
 	$(LD) -b -o $@ $< `$(CC) $(LDFLAGS) -print-libgcc-file-name`
   endif
 else
   ifeq ($(with_gnu_ld), yes)
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@ $<
+	$(CC) $(CFLAGS) $< $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@
   else
 	$(LD) -b -o $@ $<
   endif
diff --git a/src/makefiles/Makefile.linux b/src/makefiles/Makefile.linux
index f4f091caef5..ac58fe45de0 100644
--- a/src/makefiles/Makefile.linux
+++ b/src/makefiles/Makefile.linux
@@ -12,4 +12,4 @@ CFLAGS_SL = -fPIC
 
 # Rule for building a shared library from a single .o file
 %.so: %.o
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@ $<
+	$(CC) $(CFLAGS) $< $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@
diff --git a/src/makefiles/Makefile.netbsd b/src/makefiles/Makefile.netbsd
index 43841c15973..7bb9721fa5b 100644
--- a/src/makefiles/Makefile.netbsd
+++ b/src/makefiles/Makefile.netbsd
@@ -15,7 +15,7 @@ CFLAGS_SL = -fPIC -DPIC
 # Rule for building a shared library from a single .o file
 %.so: %.o
 ifdef ELF_SYSTEM
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@ $<
+	$(CC) $(CFLAGS) $< $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@
 else
 	$(LD) $(LDREL) $(LDOUT) $<.obj -x $<
 	@echo building shared object $@
diff --git a/src/makefiles/Makefile.openbsd b/src/makefiles/Makefile.openbsd
index d8fde49d5c8..eda311087cb 100644
--- a/src/makefiles/Makefile.openbsd
+++ b/src/makefiles/Makefile.openbsd
@@ -13,7 +13,7 @@ CFLAGS_SL = -fPIC -DPIC
 # Rule for building a shared library from a single .o file
 %.so: %.o
 ifdef ELF_SYSTEM
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@ $<
+	$(CC) $(CFLAGS) $< $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@
 else
 	$(LD) $(LDREL) $(LDOUT) $<.obj -x $<
 	@echo building shared object $@
diff --git a/src/makefiles/Makefile.solaris b/src/makefiles/Makefile.solaris
index e459de30cf4..a7f5652f0ca 100644
--- a/src/makefiles/Makefile.solaris
+++ b/src/makefiles/Makefile.solaris
@@ -19,9 +19,9 @@ endif
 # Rule for building a shared library from a single .o file
 %.so: %.o
 ifeq ($(GCC), yes)
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@ $<
+	$(CC) $(CFLAGS) $< $(LDFLAGS) $(LDFLAGS_SL) -shared -o $@
 else
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_SL) -G -o $@ $<
+	$(CC) $(CFLAGS) $< $(LDFLAGS) $(LDFLAGS_SL) -G -o $@
 endif
 
 sqlmansect = 5sql
diff --git a/src/test/thread/Makefile b/src/test/thread/Makefile
index f45bbda9fd9..dab1a4803fe 100644
--- a/src/test/thread/Makefile
+++ b/src/test/thread/Makefile
@@ -18,7 +18,7 @@ all: thread_test
 
 thread_test: thread_test.o
 # no need for $LIBS, might not be compiled yet
-	$(CC) $(CFLAGS) $(LDFLAGS) $(LDFLAGS_EX) $^ $(PTHREAD_LIBS) -o $@
+	$(CC) $(CFLAGS) $^ $(LDFLAGS) $(LDFLAGS_EX) $(PTHREAD_LIBS) -o $@$(X)
 
 clean distclean maintainer-clean:
 	rm -f thread_test$(X) thread_test.o