The two functions str{,n}casecmp_l are specified to be declared in
<strings.h> which is already included from <string.h> under _GNU_SOURCE.
#ifdef _GNU_SOURCE
#define strdupa(x) strcpy(alloca(strlen(x)+1),x)
int strverscmp (const char *, const char *);
#ifdef _GNU_SOURCE
#define strdupa(x) strcpy(alloca(strlen(x)+1),x)
int strverscmp (const char *, const char *);
-int strcasecmp_l (const char *, const char *, locale_t);
-int strncasecmp_l (const char *, const char *, size_t, locale_t);
char *strchrnul(const char *, int);
char *strcasestr(const char *, const char *);
void *memmem(const void *, size_t, const void *, size_t);
char *strchrnul(const char *, int);
char *strcasestr(const char *, const char *);
void *memmem(const void *, size_t, const void *, size_t);