adds shell trace to common.mk (#2538)

Common.mk

@@ -1,7 +1,5 @@
 # Disable built-in rules and variables
 MAKEFLAGS+=--no-builtin-rules --warn-undefined-variables
-SHELL=bash
-.SHELLFLAGS:=-eu -o pipefail -c
 .SUFFIXES:
 .SECONDEXPANSION:
 
@@ -14,6 +12,9 @@ PROJECT_PATH?=$(subst $(BASE_DIRECTORY)/,,$(MAKE_ROOT))
 BUILD_LIB=$(BASE_DIRECTORY)/build/lib
 OUTPUT_BIN_DIR?=$(OUTPUT_DIR)/bin/$(REPO)
 
+SHELL_TRACE?=false
+SHELL:=$(if $(filter true,$(SHELL_TRACE)),$(BUILD_LIB)/make_shell_trace.sh,bash)
+.SHELLFLAGS:=$(if $(filter true,$(SHELL_TRACE)),-c,-eu -o pipefail -c)
 #################### AWS ###########################
 AWS_REGION?=us-west-2
 AWS_ACCOUNT_ID?=$(shell aws sts get-caller-identity --query Account --output text)

Makefile

@@ -1,5 +1,12 @@
+MAKEFLAGS+=--no-builtin-rules --warn-undefined-variables
+.SUFFIXES:
+
 BASE_DIRECTORY:=$(abspath .)
 BUILD_LIB=${BASE_DIRECTORY}/build/lib
+SHELL_TRACE?=false
+SHELL:=$(if $(filter true,$(SHELL_TRACE)),$(BUILD_LIB)/make_shell_trace.sh,bash)
+.SHELLFLAGS:=$(if $(filter true,$(SHELL_TRACE)),-c,-eu -o pipefail -c)
+
 AWS_ACCOUNT_ID?=$(shell aws sts get-caller-identity --query Account --output text)
 AWS_REGION?=us-west-2
 IMAGE_REPO?=$(if $(AWS_ACCOUNT_ID),$(AWS_ACCOUNT_ID).dkr.ecr.$(AWS_REGION).amazonaws.com,localhost:5000)

build/lib/make_shell_trace.sh

@@ -0,0 +1,23 @@
+#!/usr/bin/env bash
+# Copyright Amazon.com Inc. or its affiliates. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+# remove -c passed by make
+shift
+>&2 echo "Shell trace: $@"
+eval "$@"