preprocessor: build the header out of tree

This avoids unnecessary rebuilds when we have parallel configurations
being built.

CMakeLists.txt

@@ -32,6 +32,17 @@ include_directories(${CMAKE_CURRENT_SOURCE_DIR})
 ###############################################################################
 add_library(cruft)
 
+
+# Setup a directory to hold built sources we may need to export to clients.
+set (PREFIX "cruft/util")
+file (MAKE_DIRECTORY "${CMAKE_CURRENT_BINARY_DIR}/prefix/${PREFIX}")
+target_include_directories(
+    cruft
+    PUBLIC
+    "${CMAKE_CURRENT_BINARY_DIR}/prefix/"
+)
+
+
 # Preemptively define an identity panic macro so that TCL doens't fuck us over
 # by renaming a commonly used symbol.
 target_compile_definitions(cruft PUBLIC "-Dpanic=panic")
@@ -344,7 +355,7 @@ list (
     polynomial.hpp
     pool.cpp
     pool.hpp
-    "${CMAKE_CURRENT_SOURCE_DIR}/preprocessor.hpp"
+    "${CMAKE_CURRENT_BINARY_DIR}/prefix/${PREFIX}/preprocessor.hpp"
     quaternion.cpp
     quaternion.hpp
     rand/lcg.cpp
@@ -440,13 +451,13 @@ endif ()
 ## to coax CMake into behaving here any longer. Feel free to fix it.
 add_custom_command (
 OUTPUT
-    "${CMAKE_CURRENT_SOURCE_DIR}/preprocessor.hpp"
+    "${CMAKE_CURRENT_BINARY_DIR}/prefix/${PREFIX}/preprocessor.hpp"
 COMMENT
     "[preprocessor.py] preprocessor.hpp"
 COMMAND
     "${PYTHON_EXECUTABLE}"
     "${CMAKE_CURRENT_SOURCE_DIR}/preprocessor.py"
-    "${CMAKE_CURRENT_SOURCE_DIR}/preprocessor.hpp"
+    "${CMAKE_CURRENT_BINARY_DIR}/prefix/${PREFIX}/preprocessor.hpp"
     320
 DEPENDS
     "${CMAKE_CURRENT_SOURCE_DIR}/preprocessor.py"

coord/ops.hpp

@@ -17,9 +17,10 @@
 #include "../tuple/value.hpp"
 #include "../debug.hpp"
 #include "../maths.hpp"
-#include "../preprocessor.hpp"
 #include "../types/bits.hpp"
 
+#include <cruft/util/preprocessor.hpp>
+
 #include <algorithm>
 #include <cmath>
 #include <cstdlib>

coord/store.hpp

@@ -11,9 +11,10 @@
 
 #include "fwd.hpp"
 
-#include "../preprocessor.hpp"
 #include "../platform.hpp"
 
+#include <cruft/util/preprocessor.hpp>
+
 #include <cstddef>
 #include <type_traits>
 

debug.cpp

@@ -9,7 +9,8 @@
 #include "backtrace.hpp"
 #include "debug.hpp"
 #include "log.hpp"
-#include "preprocessor.hpp"
+
+#include <cruft/util/preprocessor.hpp>
 
 #include <cstdlib>
 #include <iostream>

introspection.hpp

@@ -9,9 +9,10 @@
 #ifndef __UTIL_INTROSPECTION_HPP
 #define __UTIL_INTROSPECTION_HPP
 
-#include "preprocessor.hpp"
 #include "variadic.hpp"
 
+#include <cruft/util/preprocessor.hpp>
+
 #include <array>
 #include <cstddef>
 #include <cstdint>

log.hpp

@@ -11,9 +11,10 @@
 
 #include "nocopy.hpp"
 
-#include "preprocessor.hpp"
 #include "format.hpp"
 
+#include <cruft/util/preprocessor.hpp>
+
 #include <iosfwd>
 #include <string>
 

test/preprocessor.cpp

@@ -1,5 +1,5 @@
-#include "tap.hpp"
+#include <cruft/util/tap.hpp>
-#include "preprocessor.hpp"
+#include <cruft/util/preprocessor.hpp>
 
 
 #define PLUS(X,Y) ((X)+(Y))