Disable LLVM/Clang for riscv64

+FATAL:  fatal llvm error: Cannot select: 0x2aabd9ebd0: ch = brcond 0x2aabd9f6c8, 0x2aabd9f5f8, BasicBlock:ch<b.op.1.start 0x2aabdfc530>
+  0x2aabd9f5f8: i64 = setcc 0x2aabd9f8d0, Constant:i64<0>, setne:ch
+    0x2aabd9f8d0: i64,ch = load<(load 2 from %ir.6), zext from i16> 0x2aabdc9b48, 0x2aabd9f3f0, undef:i64
+      0x2aabd9f3f0: i64 = add nuw 0x2aabd9ee40, Constant:i64<6>
+        0x2aabd9ee40: i64,ch = load<(load 8 from %ir.3)> 0x2aabdc9b48, 0x2aabd9ed08, undef:i64
+          0x2aabd9ed08: i64 = add nuw 0x2aabd9eb68, Constant:i64<8>
+            0x2aabd9eb68: i64,ch = CopyFromReg 0x2aabdc9b48, Register:i64 %13
+              0x2aabd9eb00: i64 = Register %13
+            0x2aabd9eca0: i64 = Constant<8>
+          0x2aabd9edd8: i64 = undef
+        0x2aabd9f388: i64 = Constant<6>
+      0x2aabd9edd8: i64 = undef
+    0x2aabd9f528: i64 = Constant<0>
+In function: evalexpr_0_0
+server closed the connection unexpectedly
+	This probably means the server terminated abnormally
+	before or while processing the request.
+connection to server was lost
RPM build errors:
+ test 1 -eq 0

Signed-off-by: David Abdurachmanov <david.abdurachmanov@sifive.com>

postgresql.spec

@@ -32,7 +32,12 @@
 %{!?beta:%global beta 0}
 
 %{!?test:%global test 1}
+%ifnarch riscv64
 %{!?llvmjit:%global llvmjit 1}
+%else
+# Fail to pass tests on riscv64
+%{!?llvmjit:%global llvmjit 0}
+%endif
 %{!?upgrade:%global upgrade 1}
 %{!?plpython:%global plpython 1}
 %{!?plpython3:%global plpython3 1}
@@ -61,7 +66,7 @@ Summary: PostgreSQL client programs
 Name: postgresql
 %global majorversion 12
 Version: %{majorversion}.2
-Release: 2%{?dist}
+Release: 2.0.riscv64%{?dist}
 
 # The PostgreSQL license is very similar to other MIT licenses, but the OSI
 # recognizes it as an independent license, so we do as well.
@@ -455,6 +460,9 @@ export CFLAGS
 # since that's still considered the default plpython version.
 common_configure_options='
 	--disable-rpath
+%ifarch riscv64
+	--disable-spinlocks
+%endif
 %if %beta
 	--enable-debug
 	--enable-cassert
@@ -644,6 +652,9 @@ upgrade_configure ()
 		--host=%{_host} \
 		--prefix=%prev_prefix \
 		--disable-rpath \
+%ifarch riscv64
+		--disable-spinlocks \
+%endif
 %if %beta
 		--enable-debug \
 		--enable-cassert \
@@ -1258,6 +1269,10 @@ make -C postgresql-setup-%{setup_version} check
 
 
 %changelog
+* Sun Apr 05 2020 David Abdurachmanov <david.abdurachmanov@sifive.com> - 12.2-2.0.riscv64
+- Disable spinlocks on RISC-V 64-bit (riscv64)
+- Disable LLVM/Clang for riscv64 (fails tests)
+
 * Thu Mar 12 2020 Patrik Novotný <panovotn@redhat.com> - 12.2-2
 - Fix requirements for JIT in postgresql-server-devel
 - Fix build issues regarding new perl update