Fix PASSEDBYVALUE handling for uint8 type

Previously, we tried to parse pg_config.h to find out whether we need
to declare the uint8 type as PASSEDBYVALUE.  This turned out to be
very fragile on Red Hat-based systems, because the pg_config.h file is
in unusual places and split across several files.  The
non-PASSEDBYVALUE case is only applicable to 32-bit systems, which are
very rare nowadays.  So to simplify all this and make it more robust,
just hardcode PASSEDBYVALUE and thus drop support for 32-bit systems.

fixes #17

Makefile

@@ -9,10 +9,6 @@ ifneq (,$(indexonlyscan_supported))
 export PGOPTIONS = -c enable_indexonlyscan=off
 endif
 
-pg_config_h := $(shell $(PG_CONFIG) --includedir-server)/pg_config.h
-use_float8_byval := $(shell if grep -q 'USE_FLOAT8_BYVAL 1' $(pg_config_h) || grep -q 'SIZEOF_VOID_P 8' $(pg_config_h); then echo yes; fi)
-comma = ,
-
 extension_version = 0
 
 EXTENSION = uint
@@ -29,7 +25,7 @@ PGXS := $(shell $(PG_CONFIG) --pgxs)
 include $(PGXS)
 
 uint--$(extension_version).sql: uint.sql hash.sql hex.sql operators.sql
-	cat $^ | sed 's/@UINT8_PASSEDBYVALUE@/$(if $(use_float8_byval),PASSEDBYVALUE$(comma))/' >$@
+	cat $^ >$@
 
 PYTHON ?= python
 

README.md

@@ -12,7 +12,8 @@ This extension provides additional integer types for PostgreSQL:
 Installation
 ------------
 
-PostgreSQL version 9.1 or later is required.
+PostgreSQL version 9.1 or later is required.  Currently, only 64-bit
+builds are supported.
 
 To build and install this module:
 

uint.sql

@@ -140,7 +140,7 @@ CREATE TYPE uint8 (
     INPUT = uint8in,
     OUTPUT = uint8out,
     INTERNALLENGTH = 8,
-    @UINT8_PASSEDBYVALUE@
+    PASSEDBYVALUE,  -- requires 64-bit
     ALIGNMENT = double
 );