Add a new shell script to figure out which compiler built image.

This adds a new script that checks to see which compiler (GCC or
clang) was used to build all the images in a ChromeOS image.  It
outputs a count of how many packages it found that were built with
each compiler.

BUG=None
TEST=Tested in my chroot with both a locally-built GCC image and a
trybot-built clang image.

Change-Id: I26b5faea8616b5427c5bbe27a58ea3c9d4e36043
Reviewed-on: https://chrome-internal-review.googlesource.com/238685
Commit-Ready: Caroline Tice <cmtice@google.com>
Tested-by: Caroline Tice <cmtice@google.com>
Reviewed-by: Han Shen <shenhan@google.com>

1 files changed, 61 insertions, 0 deletions

diff --git a/compiler-test.sh b/compiler-test.sh
new file mode 100755
index 00000000..8083e2d2
--- /dev/null
+++ b/compiler-test.sh
@@ -0,0 +1,61 @@
+#!/bin/bash
+
+#  This script is supposed to verify which compiler (GCC or clang) was
+#  used to build the packages in a ChromeOS image.  To use the script,
+#  just pass the path to the tree containing the *.debug files for a
+#  ChromeOS image.  It then reads the debug info in each .debug file
+#  it can find, checking the AT_producer field to determine whether
+#  the package was built with clang or GCC.  It counts the total
+#  number of .debug files found as well as how many are built with
+#  each compiler.  It writes out these statistics when it is done.
+#
+#  For a locally-built ChromeOS image, the debug directory is usually:
+#  ${chromeos_root}/chroot/build/${board}/usr/lib/debug (from outside
+#   chroot)
+#  or
+#  /build/${board}/usr/lib/debug (from inside chroot)
+#
+#  For a buildbot-built image you can usually download the debug tree
+#  (using 'gsutil cp') from
+#  gs://chromeos-archive-image/<path-to-your-artifact-tree>/debug.tgz
+#  After downloading it somewhere, you will need to uncompress and
+#  untar it before running this script.
+#
+
+DEBUG_TREE=$1
+
+clang_count=0
+gcc_count=0
+file_count=0
+
+# Verify the argument.
+
+if [[ $# != 1 ]]; then
+    echo "Usage error:"
+    echo "compiler-test.sh <debug_directory>"
+    exit 1
+fi
+
+
+if [[ ! -d ${DEBUG_TREE} ]] ; then
+    echo "Cannot find ${DEBUG_TREE}."
+    exit 1
+fi
+
+cd ${DEBUG_TREE}
+for f in `find . -name "*.debug" -type f` ; do
+    at_producer=`readelf --debug-dump=info $f | head -25 | grep AT_producer `;
+    if echo ${at_producer} | grep -q 'GNU C' ; then
+        ((gcc_count++))
+    elif echo ${at_producer} | grep -q 'clang'; then
+        ((clang_count++));
+    fi;
+    ((file_count++))
+done
+
+echo "GCC count: ${gcc_count}"
+echo "Clang count: ${clang_count}"
+echo "Total file count: ${file_count}"
+
+
+exit 0