add script for reducing a C test case to be more minimal

test.case.reduce.sh

@@ -0,0 +1,71 @@
+#!/bin/sh -
+
+#
+# Script to reduce a test case down to a smaller set by deleting
+# lines.
+
+# Start by making the file into a single file via:
+#   cc -E -o newcfile.c -c inputfile.c
+#
+# Update the script w/ the compile command that will test for the
+# failiure you're looking for.  It is at the line marked UPDATE ME.
+#
+# And then run the script:
+#   sh test.case.reduce.sh newcfile.c
+#
+# After the run, it'll report how many lines were dropped, and
+# the final test case will be named test.c.
+#
+# This isn't perfect (I know there is a better tool out there, but
+# I can't remember/find it) in that it leaves blocks of code that
+# are multiple lines where any one removed causes an error when
+# compiling.  This can be delt w/ by hand at the end as it's a bit
+# easier, but could be improved by trying to delete n lines instead
+# of just 1 for increasing n (or maybe decreasing n?).
+#
+# In my test case of reducing, it took a 2163 line file down to
+# 313 befor manually reducing it to 18 lines.
+
+cp "$1" "test.c"
+
+totdroppedlines=0
+droppedlines=1
+while [ $droppedlines -ne 0 ]; do
+	droppedlines=0
+	i=0
+	while :; do
+		linecount=$(wc -l < test.c)
+
+		if [ $i -eq $linecount ]; then
+			break
+		fi
+
+		while [ $i -lt $linecount ]; do
+			# try to delete next line
+			(if [ $i -gt 0 ]; then head -n $i test.c; fi; tail -n +$(($i + 2)) test.c ) > curtest.c
+			#echo curtest line count: $(wc -l < curtest.c)
+
+			# modify this function such that when the test case
+			# still "fails" that it returns success.
+			#
+			# In this case, we are checking for a specific
+			# error message.
+			#
+			# ====== UPDATE ME ====== 
+			if arm-none-eabi-gcc -Werror=stringop-overflow=1 -mcpu=cortex-m3 -mthumb -O2 -g -Wall -Werror -c curtest.c  2>&1 | grep 'accessing 160 bytes in a region of size 32' > /dev/null; then
+				echo dropping line $(($i + 1 + $droppedlines))
+				droppedlines=$(($droppedlines + 1))
+				mv curtest.c test.c
+				break
+			fi
+			i=$(($i + 1))
+			echo keeping line $(($i + $droppedlines))
+		done
+	done
+
+	echo dropped $droppedlines lines
+
+	totdroppedlines=$(($totdroppedlines + $droppedlines))
+done
+
+echo dropped $totdroppedlines lines in total