PL/Perl portability fix: absorb relevant -D switches from Perl.

Back-patch of commit 3c163a7fc76debbbdad1bdd3c43721cffe72f4db,
which see for more info.

Also throw in commit b4cc35fbb709bd6fcae8998f041fd731c9acbf42,
so Coverity doesn't whine about the back branches.

Ashutosh Sharma, some adjustments by me

Discussion: https://postgr.es/m/CANFyU97OVQ3+Mzfmt3MhuUm5NwPU=-FtbNH5Eb7nZL9ua8=rcA@mail.gmail.com

4 files changed, 48 insertions, 14 deletions

diff --git a/src/Makefile.global.in b/src/Makefile.global.in
index 8ac7ca7d2bf..cb939b58551 100644
--- a/src/Makefile.global.in
+++ b/src/Makefile.global.in
@@ -298,6 +298,7 @@ else
 endif
 perl_archlibexp		= @perl_archlibexp@
 perl_privlibexp		= @perl_privlibexp@
+perl_embed_ccflags	= @perl_embed_ccflags@
 perl_embed_ldflags	= @perl_embed_ldflags@
 
 # Miscellaneous
diff --git a/src/pl/plperl/GNUmakefile b/src/pl/plperl/GNUmakefile
index b8e35852544..191f74067a6 100644
--- a/src/pl/plperl/GNUmakefile
+++ b/src/pl/plperl/GNUmakefile
@@ -12,7 +12,11 @@ override CPPFLAGS += -DPLPERL_HAVE_UID_GID
 override CPPFLAGS += -Wno-comment
 endif
 
-override CPPFLAGS := -I. -I$(srcdir) $(CPPFLAGS) -I$(perl_archlibexp)/CORE
+# Note: we need to make sure that the CORE directory is included last,
+# probably because it sometimes contains some header files with names
+# that clash with some of ours, or with some that we include, notably on
+# Windows.
+override CPPFLAGS := -I. -I$(srcdir) $(CPPFLAGS) $(perl_embed_ccflags) -I$(perl_archlibexp)/CORE
 
 rpathdir = $(perl_archlibexp)/CORE
 
diff --git a/src/pl/plperl/plperl.c b/src/pl/plperl/plperl.c
index e58c85c7b47..f4180117a58 100644
--- a/src/pl/plperl/plperl.c
+++ b/src/pl/plperl/plperl.c
@@ -3248,12 +3248,18 @@ plperl_return_next_internal(SV *sv)
 
 		/*
 		 * This is the first call to return_next in the current PL/Perl
-		 * function call, so memoize some lookups
+		 * function call, so identify the output tuple descriptor and create a
+		 * tuplestore to hold the result rows.
 		 */
 		if (prodesc->fn_retistuple)
 			(void) get_call_result_type(fcinfo, NULL, &tupdesc);
 		else
+		{
 			tupdesc = rsi->expectedDesc;
+			/* Protect assumption below that we return exactly one column */
+			if (tupdesc == NULL || tupdesc->natts != 1)
+				elog(ERROR, "expected single-column result descriptor for non-composite SETOF result");
+		}
 
 		/*
 		 * Make sure the tuple_store and ret_tdesc are sufficiently
@@ -3301,20 +3307,20 @@ plperl_return_next_internal(SV *sv)
 	}
 	else
 	{
-		Datum		ret;
-		bool		isNull;
+		Datum		ret[1];
+		bool		isNull[1];
 
-		ret = plperl_sv_to_datum(sv,
-								 prodesc->result_oid,
-								 -1,
-								 fcinfo,
-								 &prodesc->result_in_func,
-								 prodesc->result_typioparam,
-								 &isNull);
+		ret[0] = plperl_sv_to_datum(sv,
+									prodesc->result_oid,
+									-1,
+									fcinfo,
+									&prodesc->result_in_func,
+									prodesc->result_typioparam,
+									&isNull[0]);
 
 		tuplestore_putvalues(current_call_data->tuple_store,
 							 current_call_data->ret_tdesc,
-							 &ret, &isNull);
+							 ret, isNull);
 	}
 
 	MemoryContextSwitchTo(old_cxt);
diff --git a/src/tools/msvc/Mkvcbuild.pm b/src/tools/msvc/Mkvcbuild.pm
index 6285aab2b65..f3bd30540a2 100644
--- a/src/tools/msvc/Mkvcbuild.pm
+++ b/src/tools/msvc/Mkvcbuild.pm
@@ -516,7 +516,26 @@ sub mkvcbuild
 		my $plperl =
 		  $solution->AddProject('plperl', 'dll', 'PLs', 'src/pl/plperl');
 		$plperl->AddIncludeDir($solution->{options}->{perl} . '/lib/CORE');
-		$plperl->AddDefine('PLPERL_HAVE_UID_GID');
+
+		# Add defines from Perl's ccflags; see PGAC_CHECK_PERL_EMBED_CCFLAGS
+		my @perl_embed_ccflags;
+		foreach my $f (split(" ",$Config{ccflags}))
+		{
+			if ($f =~ /^-D[^_]/)
+			{
+				$f =~ s/\-D//;
+				push(@perl_embed_ccflags, $f);
+			}
+		}
+
+		# XXX this probably is redundant now?
+		push(@perl_embed_ccflags, 'PLPERL_HAVE_UID_GID');
+
+		foreach my $f (@perl_embed_ccflags)
+		{
+			$plperl->AddDefine($f);
+		}
+
 		foreach my $xs ('SPI.xs', 'Util.xs')
 		{
 			(my $xsc = $xs) =~ s/\.xs/.c/;
@@ -599,7 +618,11 @@ sub mkvcbuild
 			'hstore_plperl', 'contrib/hstore_plperl',
 			'plperl',        'src/pl/plperl',
 			'hstore',        'contrib/hstore');
-		$hstore_plperl->AddDefine('PLPERL_HAVE_UID_GID');
+
+		foreach my $f (@perl_embed_ccflags)
+		{
+			$hstore_plperl->AddDefine($f);
+		}
 	}
 
 	$mf =