unsatisfied condition: __STDC_VERSION__ >= 201112L

編譯錯誤如下：

test_cflags_cc -std=c11 ctype.h __STDC_VERSION__ >= 201112L
test_cc -std=c11
BEGIN /tmp/ffconf.yu9rN70d/test.c
    1	#include <ctype.h>
    2	#if !(__STDC_VERSION__ >= 201112L)
    3	#error "unsatisfied condition: __STDC_VERSION__ >= 201112L"
    4	#endif

解決辦法：

./configure \
    --extra-cflags="-std=11"