scripts: set clang as REAL_CC to support LLVM by default

To support LLVM by default, set REAL_CC to clang which overrides
gcc.

Also, white list warnings which are being treated as errors
while compiling Kernel with clang compiler.

Change-Id: I5df2375cb8a2f424521fdd862d550ab340a34c98
Signed-off-by: Satya Durga Srinivasu Prabhala <satyap@codeaurora.org>
Signed-off-by: Naitik Bharadiya <bharad@codeaurora.org>

1 files changed, 14 insertions, 5 deletions

diff --git a/scripts/build-all.py b/scripts/build-all.py
index 4f02c33d4248..a3ac915099c1 100755
--- a/scripts/build-all.py
+++ b/scripts/build-all.py
@@ -1,6 +1,6 @@
 #! /usr/bin/env python2
 
-# Copyright (c) 2009-2015, The Linux Foundation. All rights reserved.
+# Copyright (c) 2009-2015, 2017, 2019, The Linux Foundation. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are met:
@@ -45,6 +45,7 @@ build_dir = '../all-kernels'
 make_command = ["vmlinux", "modules", "dtbs"]
 all_options = {}
 compile64 = os.environ.get('CROSS_COMPILE64')
+clang_bin = os.environ.get('CLANG_BIN')
 
 def error(msg):
     sys.stderr.write("error: %s\n" % msg)
@@ -269,10 +270,18 @@ class Builder():
         if not all_options.updateconfigs:
             # Build targets can be dependent upon the completion of
             # previous build targets, so build them one at a time.
-            cmd_line = ['make',
-                'INSTALL_HDR_PATH=%s' % hdri_dir,
-                'INSTALL_MOD_PATH=%s' % modi_dir,
-                'O=%s' % dest_dir]
+            if os.environ.get('ARCH') == "arm64":
+                cmd_line = ['make',
+                    'INSTALL_HDR_PATH=%s' % hdri_dir,
+                    'INSTALL_MOD_PATH=%s' % modi_dir,
+                    'O=%s' % dest_dir,
+                    'REAL_CC=%s' % clang_bin]
+            else:
+                cmd_line = ['make',
+                    'INSTALL_HDR_PATH=%s' % hdri_dir,
+                    'INSTALL_MOD_PATH=%s' % modi_dir,
+                    'O=%s' % dest_dir]
+
             build_targets = []
             for c in make_command:
                 if re.match(r'^-{1,2}\w', c):