From a5fd0f039fa3d067d641595e4043dd5e8e3c0820 Mon Sep 17 00:00:00 2001
From: Mikko Rasa <tdb@tdb.fi>
Date: Fri, 1 Dec 2017 13:08:09 +0200
Subject: [PATCH] Interrogate the compiler for the system path

Rather than trying to guesstimate it from the compiler version.
---
 source/androidcompiler.cpp | 18 ++++++++++++++
 source/gnucompiler.cpp     | 49 ++++++++++++++++++++++----------------
 source/gnucompiler.h       |  3 ---
 3 files changed, 47 insertions(+), 23 deletions(-)

diff --git a/source/androidcompiler.cpp b/source/androidcompiler.cpp
index 490c198..53f4de1 100644
--- a/source/androidcompiler.cpp
+++ b/source/androidcompiler.cpp
@@ -1,9 +1,13 @@
 #include <msp/fs/dir.h>
 #include <msp/fs/stat.h>
+#include <msp/fs/utils.h>
 #include <msp/strings/format.h>
+#include <msp/strings/utils.h>
 #include "androidcompiler.h"
 #include "androidtools.h"
 #include "builder.h"
+#include "externaltask.h"
+#include "filetarget.h"
 
 using namespace std;
 using namespace Msp;
@@ -23,6 +27,20 @@ void AndroidCompiler::do_prepare()
 	GnuCompiler::do_prepare();
 	if(executable && tag=="CXX")
 	{
+		ExternalTask::Arguments argv;
+		argv.push_back(executable->get_path().str());
+		argv.push_back("-dumpversion");
+
+		builder.get_logger().log("auxcommands", format("Running %s", join(argv.begin(), argv.end())));
+		string version;
+		try
+		{
+			version = strip(ExternalTask::run_and_capture_output(argv));
+			builder.get_logger().log("tools", format("%s version is %s", FS::basename(executable->get_path()), version));
+		}
+		catch(const runtime_error &)
+		{ }
+
 		FS::Path libstdcxx_path = ndk.get_root_dir()/"sources"/"cxx-stl"/"gnu-libstdc++"/version;
 
 		FS::Path public_dir = libstdcxx_path/"include";
diff --git a/source/gnucompiler.cpp b/source/gnucompiler.cpp
index ea04fbe..8d0bca7 100644
--- a/source/gnucompiler.cpp
+++ b/source/gnucompiler.cpp
@@ -1,6 +1,4 @@
 #include <msp/core/maputils.h>
-#include <msp/fs/dir.h>
-#include <msp/fs/stat.h>
 #include <msp/fs/utils.h>
 #include <msp/strings/format.h>
 #include <msp/strings/utils.h>
@@ -54,14 +52,7 @@ GnuCompiler::GnuCompiler(Builder &b, const Architecture &a, const string &t, con
 	set_command((tag=="CXX" ? "g++" : "gcc"), true);
 
 	if(!sysroot.empty())
-	{
 		build_info.sysroot = sysroot;
-		system_path.push_back(sysroot/"usr/include");
-	}
-	else if(architecture->is_native())
-		system_path.push_back("/usr/include");
-	else
-		system_path.push_back("/usr/"+architecture->get_cross_prefix()+"/include");
 }
 
 Target *GnuCompiler::create_source(const Component &comp, const FS::Path &path) const
@@ -116,24 +107,42 @@ void GnuCompiler::do_prepare()
 	{
 		ExternalTask::Arguments argv;
 		argv.push_back(executable->get_path().str());
-		argv.push_back("-dumpversion");
+		argv.push_back("-Wp,-v");
+		argv.push_back("-E");
+		if(tag=="CXX")
+			argv.push_back("-xc++");
+		const FS::Path &sysroot = build_info.sysroot;
+		if(!sysroot.empty())
+			argv.push_back("--sysroot="+sysroot.str());
+		argv.push_back("-");
 
+		string prog = FS::basename(executable->get_path());
 		builder.get_logger().log("auxcommands", format("Running %s", join(argv.begin(), argv.end())));
 		try
 		{
-			version = strip(ExternalTask::run_and_capture_output(argv));
-			builder.get_logger().log("tools", format("%s version is %s", FS::basename(executable->get_path()), version));
-
-			if(tag=="CXX")
+			string output = ExternalTask::run_and_capture_output(argv, FS::Path(), true);
+			string::size_type start = 0;
+			bool record_path = false;
+			while(start<output.size())
 			{
-				const FS::Path &sysroot = build_info.sysroot;
-				FS::Path cxx_path = sysroot/"usr"/"include"/"c++"/version;
-				if(FS::is_dir(cxx_path))
-					system_path.push_back(cxx_path);
+				string::size_type newline = output.find('\n', start);
+				if(!output.compare(start, 34, "#include <...> search starts here:"))
+					record_path = true;
+				else if(!output.compare(start, 19, "End of search list."))
+					record_path = false;
+				else if(record_path)
+				{
+					FS::Path path = strip(output.substr(start, newline-start));
+					builder.get_logger().log("tools", format("Got %s (%s) system path: %s", prog, tag, path));
+					system_path.push_back(path);
+				}
+				start = newline+1;
 			}
 		}
-		catch(const runtime_error &)
-		{ }
+		catch(const runtime_error &e)
+		{
+			problems.push_back("Unable to determine system path");
+		}
 	}
 }
 
diff --git a/source/gnucompiler.h b/source/gnucompiler.h
index 0eb25d0..4b82e6f 100644
--- a/source/gnucompiler.h
+++ b/source/gnucompiler.h
@@ -12,9 +12,6 @@ appropriate type.
 */
 class GnuCompiler: public Tool
 {
-protected:
-	std::string version;
-
 public:
 	GnuCompiler(Builder &, const Architecture &, const std::string &, const Msp::FS::Path & = Msp::FS::Path());
 
-- 
2.43.0