diff --git a/build_rts.py b/build_rts.py
index 5879df00..02b89d1d 100755
--- a/build_rts.py
+++ b/build_rts.py
@@ -49,7 +49,8 @@
 from x86_64 import X8664Generic
 
 # native
-from native import Aarch64Native, X86Native, X8664Native
+from linux import Aarch64Linux, X86Linux, X8664Linux
+from windows import X86Windows, X8664Windows
 
 # vx7r2cert
 from vx7r2cert import AArch64Vx7r2Cert, ArmVx7r2Cert, \
@@ -224,12 +225,16 @@ def build_configs(target):
     elif target == 'x86_64':
         t = X8664Generic()
     # native platforms
-    elif target in ('x86-linux', 'x86-windows'):
-        t = X86Native()
-    elif target in ('x86_64-linux', 'x86_64-windows', 'x86_64-windows64'):
-        t = X8664Native()
-    elif target in ('aarch64-linux',):
-        t = Aarch64Native()
+    elif target == "aarch64-linux":
+        t = Aarch64Linux()
+    elif target == "x86-linux":
+        t = X86Linux()
+    elif target == "x86_64-linux":
+        t = X8664Linux()
+    elif target == "x86-windows":
+        t = X86Windows()
+    elif target in ("x86_64-windows", "x86_64-windows64"):
+        t = X8664Windows()
     # vx7r2cert
     elif target == "aarch64-vx7r2cert":
         t = AArch64Vx7r2Cert()
diff --git a/gen_rts_sources.py b/gen_rts_sources.py
index 8242ae31..30a179b8 100755
--- a/gen_rts_sources.py
+++ b/gen_rts_sources.py
@@ -44,7 +44,8 @@ def main():
         '--rts-profile', choices=['light', 'light-tasking', 'embedded', 'cert'],
         required=True,  help='supported profiles')
     parser.add_argument(
-        '--source-profile', choices=['bb', 'deos', 'pikeos', 'vx7r2cert', 'qnx'],
+        '--source-profile',
+        choices=['bb', 'deos', 'linux', 'pikeos', 'vx7r2cert', 'qnx'],
         default='bb', help='platform specific source selections')
 
     args = parser.parse_args()
diff --git a/native/__init__.py b/linux/__init__.py
similarity index 65%
rename from native/__init__.py
rename to linux/__init__.py
index 8470acf2..968de20c 100644
--- a/native/__init__.py
+++ b/linux/__init__.py
@@ -1,20 +1,19 @@
 from support.bsp_sources.target import DFBBTarget
 
 
-class Native(DFBBTarget):
+class Linux(DFBBTarget):
     def __init__(self):
         super().__init__()
-        self.add_gnat_sources(
-            'src/s-macres__native.adb',
-            'src/s-textio__stdio.adb')
-
-    @property
-    def target(self):
-        return None
+        self.add_gnat_sources("src/s-macres__native.adb")
+        self.add_gnarl_sources("linux/adaint.c")
 
     def has_libc(self, profile):
         return True
 
+    @property
+    def name(self):
+        return self.target
+
     def dump_runtime_xml(self, rts_name, rts):
         return ('<?xml version="1.0" ?>\n'
                 '<gprconfig>\n'
@@ -22,24 +21,25 @@ def dump_runtime_xml(self, rts_name, rts):
                 '  </configuration>\n'
                 '</gprconfig>\n')
 
-    def amend_rts(self, rts_profile, cfg):
-        super().amend_rts(rts_profile, cfg)
+    @property
+    def is_legacy_format(self):
+        return True
 
 
-class X86Native(Native):
+class X86Linux(Linux):
     @property
-    def name(self):
-        return 'native-x86'
+    def target(self):
+        return "x86-linux"
 
     @property
     def system_ads(self):
         return {'light': 'system-xi-x86.ads'}
 
 
-class X8664Native(Native):
+class X8664Linux(Linux):
     @property
-    def name(self):
-        return 'native-x86_64'
+    def target(self):
+        return "x86_64-linux"
 
     @property
     def is_64bit(self):
@@ -50,10 +50,10 @@ def system_ads(self):
         return {'light': 'system-xi-x86_64.ads'}
 
 
-class Aarch64Native(Native):
+class Aarch64Linux(Linux):
     @property
-    def name(self):
-        return 'native-aarch64'
+    def target(self):
+        return "aarch64-linux"
 
     @property
     def is_64bit(self):
diff --git a/linux/adaint.c b/linux/adaint.c
new file mode 100644
index 00000000..3e431e05
--- /dev/null
+++ b/linux/adaint.c
@@ -0,0 +1,44 @@
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+#include <sys/syscall.h>
+#include <unistd.h>
+#include <sched.h>
+
+void *
+__gnat_lwp_self (void)
+{
+   return (void *) syscall (__NR_gettid);
+}
+
+cpu_set_t *
+__gnat_cpu_alloc (size_t count)
+{
+  return CPU_ALLOC (count);
+}
+
+size_t
+__gnat_cpu_alloc_size (size_t count)
+{
+  return CPU_ALLOC_SIZE (count);
+}
+
+void
+__gnat_cpu_free (cpu_set_t *set)
+{
+  CPU_FREE (set);
+}
+
+void
+__gnat_cpu_zero (size_t count, cpu_set_t *set)
+{
+  CPU_ZERO_S (count, set);
+}
+
+void
+__gnat_cpu_set (int cpu, size_t count, cpu_set_t *set)
+{
+  /* Ada handles CPU numbers starting from 1, while C identifies the first
+     CPU by a 0, so we need to adjust. */
+  CPU_SET_S (cpu - 1, count, set);
+}
diff --git a/support/data/target_options.gpr.in b/support/data/target_options.gpr.in
index 1b29d4ce..9acf7fea 100644
--- a/support/data/target_options.gpr.in
+++ b/support/data/target_options.gpr.in
@@ -52,8 +52,8 @@ abstract project Target_Options is
         --  link against libgnat (itself).
         --  Since -nostdlib also removes libgcc
         --  from the linked libraries we have to
-        --  add -lgcc again.
-        LOPTIONS := LOPTIONS & ("-nostdlib", "-lgcc");
+        --  add -lc and -lgcc again.
+        LOPTIONS := LOPTIONS & ("-nostdlib", "-lc", "-lgcc");
   end case;
 
   --  Concatenate with common flags
diff --git a/support/rts_sources/sources.py b/support/rts_sources/sources.py
index 4d489259..a4953346 100644
--- a/support/rts_sources/sources.py
+++ b/support/rts_sources/sources.py
@@ -229,6 +229,16 @@
             'hie/a-textio__deos.ads', 'hie/a-textio__deos.adb',
             'hie/s-macres.ads',
              ],
+        'linux_srcs': [
+            'hie/a-textio.ads',
+            'hie/a-textio__libc.adb',
+            'hie/g-io__zfp.ads',
+            'hie/g-io__zfp.adb',
+            'hie/g-io-put.adb',
+            'hie/s-macres.ads',
+            'hie/s-textio__libc.ads',
+            'hie/s-textio__libc.adb',
+        ],
         'pikeos_srcs': [
             'hie/a-textio.ads',
             'exit.c',
@@ -246,11 +256,15 @@
             'vx_stack_info.c'],
         'qnx_srcs': [
             'exit.c',
-            'hie/g-io__zfp.ads', 'hie/g-io__zfp.adb',
+            'hie/g-io__zfp.ads',
+            'hie/g-io__zfp.adb',
             'hie/g-io-put.adb',
-            'hie/a-textio.ads', 'hie/a-textio__qnx.adb',
+            'hie/a-textio.ads',
+            'hie/a-textio__qnx.adb',
             'hie/s-macres.ads',
-            'hie/s-textio__qnx.ads', 'hie/s-textio__qnx.adb']
+            'hie/s-textio__qnx.ads',
+            'hie/s-textio__qnx.adb'
+        ],
     },
 
     'common/32': {
@@ -282,6 +296,7 @@
             'hie/s-assert__xi.adb',
             'hie/s-memory__light.ads'],
         'bb_srcs': ['hie/a-elchha__zfp.adb'],
+        'linux_srcs': ['hie/a-elchha__zfp.adb'],
         'pikeos_srcs': ['hie/a-elchha__zfp.adb'],
         'qnx_srcs': [
             'hie/a-elchha__traceback.adb',
@@ -307,6 +322,7 @@
             'hie/s-sssita.ads', 'hie/s-sssita.adb'],
         'deos_srcs': [
             'hie/s-thread__cert.ads', 'hie/s-thread__cert.adb'],
+        'linux_srcs': ['hie/s-sssita.ads', 'hie/s-sssita.adb'],
         'pikeos_srcs': [
             'hie/a-textio__pikeos-light.adb',
             'hie/s-sssita.ads', 'hie/s-sssita.adb'],
@@ -1048,6 +1064,19 @@
             'hie/a-nalofl__light.ads',
             'hie/a-nallfl__light.ads',
             'libgnat/a-naliop__nolibm.ads'],
+        'linux_srcs': [
+            'hie/a-ngelfu__cert.ads',
+            'hie/a-ngelfu__cert.adb',
+            'hie/a-nlelfu__cert.ads',
+            'hie/a-nuelfu__cert.ads',
+            'hie/s-gcmain__cert.ads',
+            'hie/s-gcmain__cert.adb',
+            'hie/a-nllefu__cert.ads',
+            'hie/a-nuaufl__light.ads',
+            'hie/a-nalofl__light.ads',
+            'hie/a-nallfl__light.ads',
+            'libgnat/a-naliop.ads',
+        ],
         'pikeos_srcs': [
             'hie/a-ngelfu__ada.ads', 'hie/a-ngelfu__ada.adb',
             'hie/a-nlelfu__ada.ads',
@@ -1713,15 +1742,18 @@
     },
     'gnat/parameters/light-small': {
         'conditions': ['RTS_Profile:light', 'Memory_Profile:small'],
-        'bb_srcs': ['hie/s-parame__zfp_small.ads']
+        'bb_srcs': ['hie/s-parame__zfp_small.ads'],
+        'linux_srcs': ['hie/s-parame__zfp_small.ads'],
     },
     'gnat/parameters/light-large': {
         'conditions': ['RTS_Profile:light', 'Memory_Profile:large'],
-        'bb_srcs': ['hie/s-parame__zfp.ads']
+        'bb_srcs': ['hie/s-parame__zfp.ads'],
+        'linux_srcs': ['hie/s-parame__zfp.ads'],
     },
     'gnat/parameters/light-huge': {
         'conditions': ['RTS_Profile:light', 'Memory_Profile:huge'],
-        'bb_srcs': ['hie/s-parame__zfp_huge.ads']
+        'bb_srcs': ['hie/s-parame__zfp_huge.ads'],
+        'linux_srcs': ['hie/s-parame__zfp_huge.ads'],
     },
 
     # Cert
diff --git a/windows/__init__.py b/windows/__init__.py
new file mode 100644
index 00000000..4e7ce7a1
--- /dev/null
+++ b/windows/__init__.py
@@ -0,0 +1,51 @@
+from support.bsp_sources.target import DFBBTarget
+
+
+class Windows(DFBBTarget):
+    def __init__(self):
+        super().__init__()
+        self.add_gnat_sources("src/s-macres__native.adb", "src/s-textio__stdio.adb")
+
+    @property
+    def name(self):
+        return self.target
+
+    def has_libc(self, profile):
+        return True
+
+    def dump_runtime_xml(self, rts_name, rts):
+        return (
+            '<?xml version="1.0" ?>\n'
+            "<gprconfig>\n"
+            "  <configuration>\n"
+            "  </configuration>\n"
+            "</gprconfig>\n"
+        )
+
+    @property
+    def is_legacy_format(self):
+        return True
+
+
+class X86Windows(Windows):
+    @property
+    def target(self):
+        return "x86-windows"
+
+    @property
+    def system_ads(self):
+        return {"light": "system-native-x86-light.ads"}
+
+
+class X8664Windows(Windows):
+    @property
+    def target(self):
+        return "x86_64-windows"
+
+    @property
+    def is_64bit(self):
+        return True
+
+    @property
+    def system_ads(self):
+        return {"light": "system-native-x86-light.ads"}