gecko/config/find_vanilla_new_calls

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# /bin/bash
#----------------------------------------------------------------------------
# We must avoid using the vanilla new/new[] operators (and consequently, the
# vanilla delete/delete[] operators) in SpiderMonkey, see bug 624878 for why.
#
# This script:
# - Detects if any of the vanilla new/new[] operators are used in a file.
# Its exit code is 1 if it found some, and 0 if it didn't.
# - Doesn't detect delete/delete[] because it appears they can be present
# somehow due to virtual destructors, but this is ok because vanilla
# delete/delete[] calls don't make sense without corresponding new/new[]
# calls, and any explicit calls will be caught by Valgrind's mismatched
# alloc/free checking.
# - Doesn't detect the 'nothrow' variants, which are ok but probably still
# best avoided.
# - Is designed to only run on Linux (though it may also work on Mac); one
# platform will be enough to catch any violations.
#
# If this script fails:
# - You need to find the uses of vanilla new/delete and replace them with
# {js::OffTheBooks,JSContext,JSRuntime}::{new_,/array_new}.
# - Run this script on each of the .o files, that should narrow it down.
# - After that, one way to find them is to run 'objdump -r -C' on the
# relevant .o files. For example, you might search for 'operator new' and
# find a record like this:
#
# RELOCATION RECORDS FOR [.text._ZN3JSC14ExecutablePool6createEj]:
# OFFSET TYPE VALUE
# 00000009 R_386_PC32 __i686.get_pc_thunk.bx
# 0000000f R_386_GOTPC _GLOBAL_OFFSET_TABLE_
# 0000001b R_386_PLT32 operator new(unsigned int)
# 0000002e R_386_PC32 JSC::ExecutablePool::ExecutablePool(unsigned int)
# 0000004a R_386_PC32 JSC::ExecutablePool::~ExecutablePool()
# 00000052 R_386_PLT32 operator delete(void*)
#
# This says that vanilla 'new' and 'delete' are both used in
# JSC::ExecutablePool::create(unsigned int). This doesn't always work,
# though. (Nb: use 'c++filt' to demangle names like
# _ZN3JSC14ExecutablePool6createEj.)
#
# If that doesn't work, use grep.
#----------------------------------------------------------------------------
if [ -z $1 ] ; then
echo "usage: find_vanilla_new_calls <file>"
exit 1
fi
file=$1
if [ ! -f $file ] ; then
echo "TEST-UNEXPECTED-FAIL | find_vanilla_new_calls | file '$file' not found"
exit 1
fi
tmpfile1=`mktemp`
tmpfile2=`mktemp`
nm -C $file > $tmpfile1
# Need to double-escape '[' and ']' to stop grep from interpreting them
# specially.
grep 'operator new(unsigned int)' $tmpfile1 >> $tmpfile2
grep 'operator new(unsigned long)' $tmpfile1 >> $tmpfile2
grep 'operator new\\[\\](unsigned int)' $tmpfile1 >> $tmpfile2
grep 'operator new\\[\\](unsigned long)' $tmpfile1 >> $tmpfile2
rm -f $tmpfile1
if [ -s $tmpfile2 ] ; then
echo "TEST-UNEXPECTED-FAIL | find_vanilla_new_calls | found calls are listed below"
cat $tmpfile2
echo
rm -f $tmpfile2
exit 1
fi
echo "TEST-PASS | find_vanilla_new_calls | ok"
echo
exit 0