Bash script hanging when running tests

Question

So I am writing a git hook, which calls a script to run some tests in the background. The problem is that the script never goes beyond the exec when the test fails.

The beggining of the script

#!/usr/bin/env bash
set -x
## 4 ##
full_path="$1/$2"
cd $full_path
BODY=""
make > build.log 2> build.error
if [ $?  -eq 0 ]; then
    ## 5 ##
    PASSED=0
    FAILED=0
    for line in $(find . -name '*test*' -executable -type f); do
        out="${line:2}.log" 
        error="${line:2}.error"
        exec $line > $out 2> $error
        echo "I AM ALIVE"
        if [ $? -eq 0 ]; then
            ((PASSED++))
        else
            ((FAILED++))    

And the contents of the error file

cat tree_insert_test.error 
tree_insert_test: p2.cpp:69: tree_t insert_tree(int, tree_t): Assertion `false' failed.