Make GCC fully relocatable, not searching any fixed paths

From: J.M. Eubank <john@thesnappy.net>

that aren't relative to the current installation path

# HG changeset patch
# Parent 2a1167ee4ed20c6ff3558a104218585837e9963f
---
 0 files changed

diff --git a/gcc/config/i386/mingw32.h b/gcc/config/i386/mingw32.h
index 086c0e460..f0ceca42b 100644
--- a/gcc/config/i386/mingw32.h
+++ b/gcc/config/i386/mingw32.h
@@ -78,7 +78,7 @@ along with GCC; see the file COPYING3.  If not see
 #endif
 
 #undef NATIVE_SYSTEM_HEADER_COMPONENT
-#define NATIVE_SYSTEM_HEADER_COMPONENT "MINGW"
+#undef NATIVE_SYSTEM_HEADER_DIR
 
 #undef CPP_SPEC
 #define CPP_SPEC "%{posix:-D_POSIX_SOURCE} %{mthreads:-D_MT} " \
@@ -183,17 +183,12 @@ along with GCC; see the file COPYING3.  If not see
 
 /* Override startfile prefix defaults.  */
 #ifndef STANDARD_STARTFILE_PREFIX_1
-#define STANDARD_STARTFILE_PREFIX_1 "/mingw/lib/"
+#define STANDARD_STARTFILE_PREFIX_1 ""
 #endif
 #ifndef STANDARD_STARTFILE_PREFIX_2
 #define STANDARD_STARTFILE_PREFIX_2 ""
 #endif
 
-/* For native mingw-version we need to take care that NATIVE_SYSTEM_HEADER_DIR
-   macro contains POSIX-style path.  See bug 52947.  */
-#undef NATIVE_SYSTEM_HEADER_DIR
-#define NATIVE_SYSTEM_HEADER_DIR "/mingw/include"
-
 /* Output STRING, a string representing a filename, to FILE.
    We canonicalize it to be in Unix format (backslashes are replaced
    forward slashes.  */
diff --git a/gcc/incpath.c b/gcc/incpath.c
index bcbe20829..c5d4453d8 100644
--- a/gcc/incpath.c
+++ b/gcc/incpath.c
@@ -183,8 +183,7 @@ add_standard_paths (const char *sysroot, const char *iprefix,
 	      str = concat (sysroot_no_trailing_dir_separator, p->fname, NULL);
 	      free (sysroot_no_trailing_dir_separator);
 	    }
-	  else if (!p->add_sysroot && relocated
-		   && !filename_ncmp (p->fname, cpp_PREFIX, cpp_PREFIX_len))
+	  if (relocated && !filename_ncmp (p->fname, cpp_PREFIX, cpp_PREFIX_len))
 	    {
  	      static const char *relocated_prefix;
 	      char *ostr;