From 79711be46a76e5ecc64894bc1832637d5e34efe3 Mon Sep 17 00:00:00 2001
From: "Justin C. Miller" <justin@devjustinian.com>
Date: Thu, 7 Feb 2019 17:39:10 -0800
Subject: [PATCH] Dump compiler args and defines.

As part of the build, dump the compiler arguments and defines per target
into files.
---
 scripts/templates/build.ninja.j2    | 22 ++++++++++++++++++++++
 scripts/templates/target.default.j2 |  7 +++++++
 2 files changed, 29 insertions(+)

diff --git a/scripts/templates/build.ninja.j2 b/scripts/templates/build.ninja.j2
index c80da08..2c57dc6 100644
--- a/scripts/templates/build.ninja.j2
+++ b/scripts/templates/build.ninja.j2
@@ -53,12 +53,34 @@ rule cc
     description = Compiling $name
     command = $cc -MMD -MF $out.d $ccflags $cflags -o $out -c $in
 
+rule dump_cc_defs
+    description = Dumping CC defines for $target
+    command = echo "" | $cc $ccflags $cflags -dM -E - > $out
+
+rule dump_cc_run
+    description = Dumping CC arguments for $target
+    command = $
+        echo "#!/bin/bash" > $out; $
+        echo '$cc $ccflags $cflags $$*' > $out; $
+        chmod a+x $out
+
 rule cxx
     deps = gcc
     depfile = $out.d
     description = Compiling $name
     command = $cxx -MMD -MF $out.d $cxxflags $ccflags -o $out -c $in
 
+rule dump_cxx_defs
+    description = Dumping C++ defines for $target
+    command = echo "" | $cxx -x c++ $cxxflags $ccflags -dM -E - > $out
+
+rule dump_cxx_run
+    description = Dumping C++ arguments for $target
+    command = $
+        echo "#!/bin/bash" > $out; $
+        echo '$cc $cxxflags $ccflags $$*' > $out; $
+        chmod a+x $out
+
 rule nasm
     deps = gcc
     depfile = $out.d
diff --git a/scripts/templates/target.default.j2 b/scripts/templates/target.default.j2
index 93098ef..31c9191 100644
--- a/scripts/templates/target.default.j2
+++ b/scripts/templates/target.default.j2
@@ -1,4 +1,5 @@
 builddir = $builddir/{{ target }}
+target = {{ target }}
 
 {% block variables %}
 {% endblock %}
@@ -15,3 +16,9 @@ objcopy = objcopy
 {% for module in modules %}
 subninja {{ module.name }}.ninja
 {% endfor %}
+
+build ${builddir}/cc.defs : dump_cc_defs | {{ buildfile }}
+build ${builddir}/cxx.defs : dump_cxx_defs | {{ buildfile }}
+build ${builddir}/cc.run : dump_cc_run | {{ buildfile }}
+build ${builddir}/cxx.run : dump_cxx_run | {{ buildfile }}
+