Add an option for system header dependencies.

This is suitable for those developing tools.  It is not an option that is worth
enabling for those doing regular RTEMS development.

4 files changed, 14 insertions, 2 deletions

diff --git a/rtems_waf/config/base.py b/rtems_waf/config/base.py
index e789a1e022..10b2d848bb 100644
--- a/rtems_waf/config/base.py
+++ b/rtems_waf/config/base.py
@@ -205,7 +205,7 @@ class cfg_bsp(Config):
 		c.LINK_START			= Default
 		c.LINK_END				= Default
 		c.LINK_LINK				= Default
-
+		c.ENABLE_SYSTEM_DEP		= Default
 
 
 
diff --git a/rtems_waf/configure.py b/rtems_waf/configure.py
index aceb0a5518..94be70e13e 100644
--- a/rtems_waf/configure.py
+++ b/rtems_waf/configure.py
@@ -201,7 +201,6 @@ def build_config(ctx):
 
 
 def cmd_configure(ctx, config):
-
 	ctx.load('waf', tooldir='rtems_waf')
 
 	from rtems_waf.config import BuildConfig
@@ -310,6 +309,11 @@ def cmd_configure(ctx, config):
 	# Always start with a pristeen env while looping.
 	env_orig = ctx.env
 	for bsp in ctx.env.BSP:
+
+#		if ctx.env.ENABLE_SYSTEM_DEP:
+#			from waflib.Tools import c_preproc
+#			c_preproc.go_absolute=True
+
 		msg("")
 		msg("--- Configuring %s ---" % bsp)
 		ctx.setenv(bsp, env_orig.derive())
diff --git a/rtems_waf/defaults/options.py b/rtems_waf/defaults/options.py
index 8ecc675ad9..2cf1af7a72 100644
--- a/rtems_waf/defaults/options.py
+++ b/rtems_waf/defaults/options.py
@@ -2349,3 +2349,8 @@ class CONSOLE_BAUD(Integer):
 	undef = True
 	descr = "initial baud for console UART"
 
+
+class ENABLE_SYSTEM_DEP(Boolean):
+	value	= False
+	undef	= True
+	descr	= "Enable dependencies on system headers, only useful if you are developing toolchains.  This will slow down the build"
diff --git a/wscript b/wscript
index 5ce156a1d6..4eaac72901 100644
--- a/wscript
+++ b/wscript
@@ -148,6 +148,9 @@ def configure(ctx):
 
 
 def build(ctx):
+	if ctx.env.ENABLE_SYSTEM_DEP:
+		c_preproc.go_absolute=True
+
 	if ctx.env.CONFIG_TIMESTAMP != get_file_mtime("config.cfg"):
 		ctx.fatal("config.cfg has changed please re-run 'waf configure'")