参考 Thread-safety in the ARM C libraries

libstdc++ Thread Safety

# gcc -v
Using built-in specs.
...
Thread model: posix
gcc version 4.1.2 20070925 (Red Hat 4.1.2-33)

Look for "Thread model" lines that aren't equal to "single."

"Thread model" 不等于 "single" 代表线程安全