This patch fixes a "set but not used" warning in setjmp/jmpbug.c. A
variable is used only to store the result of alloca. A cast to void
is added to avoid the warning, and the variable is made volatile to
ensure the call to alloca isn't optimized away for being unused.
Tested for x86_64.
* setjmp/jmpbug.c (test): Make foo volatile and cast it to
void.
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