Re: [uclibc-ng-devel] doubts over defines of __USE_MISC and __DEFAULT_SOURCE

Cancel the previous... I must have been staring at the wrong thing. Cause is TOTALLY different OK, to recap: Compiling zstd-1.4.5 using uclibc-ng, will trigger an error in programs/util.c which basically indicates that the section "struct stat" in bits/stat.h relating to the definitions of "st_mtim" are hidden behind "#define __USE_MISC" I have prepared a patch that I'm about to send upstream to zstd which will add a declare for __USE_MISC and this allows compilation... BUT... The underlying reason appears to be that in glibc, the relevant section of <bits/stat.h> reads as follows #ifdef __USE_XOPEN2K8     /* Nanosecond resolution timestamps are stored in a format        equivalent to 'struct timespec'.  This is the type used        whenever possible but the Unix namespace rules do not allow the        identifier 'timespec' to appear in the <sys/stat.h> header.        Therefore we have to handle the use of this header in strictly        standard-compliant sources special.  */     struct timespec st_atim;            /* Time of last access. */     struct timespec st_mtim;            /* Time of last modification.  */     struct timespec st_ctim;            /* Time of last status change.  */ # define st_atime st_atim.tv_sec        /* Backward compatibility.  */ # define st_mtime st_mtim.tv_sec # define st_ctime st_ctim.tv_sec #else So it's hidden behind "#ifdef __USE_XOPEN2K8", whereas in uclibc_ng we have: #ifdef __USE_MISC     /* Nanosecond resolution timestamps are stored in a format        equivalent to 'struct timespec'.  This is the type used        whenever possible but the Unix namespace rules do not allow the        identifier 'timespec' to appear in the <sys/stat.h> header.        Therefore we have to handle the use of this header in strictly        standard-compliant sources special.  */     struct timespec st_atim;            /* Time of last access. */     struct timespec st_mtim;            /* Time of last modification.  */     struct timespec st_ctim;            /* Time of last status change.  */ # define st_atime st_atim.tv_sec        /* Backward compatibility.  */ # define st_mtime st_mtim.tv_sec # define st_ctime st_ctim.tv_sec #else Now, I have no idea what is supposed to happen, but in glibc, this is all turned on by: #if defined _POSIX_C_SOURCE && (_POSIX_C_SOURCE - 0) >= 200809L # define __USE_XOPEN2K8         1 We have the same stanzas in uclibc_ng, but they don't have the same effects, nor do they define __USE_MISC I believe that the solution is the following patch? Could someone more knowledgeable than me check this and make an appropriate change please? --- a/bits/stat.h    2020-06-16 14:10:25.789364391 +0000 +++ b/bits/stat.h    2020-07-06 15:34:49.221988579 +0000 @@ -61,7 +61,7 @@  #else      __blkcnt64_t st_blocks;        /* Number 512-byte blocks allocated. */  #endif -#ifdef __USE_MISC +#ifdef __USE_XOPEN2K8      /* Nanosecond resolution timestamps are stored in a format         equivalent to 'struct timespec'.  This is the type used         whenever possible but the Unix namespace rules do not allow the @@ -107,7 +107,7 @@      __blksize_t st_blksize;        /* Optimal block size for I/O.  */      __blkcnt64_t st_blocks;        /* Number 512-byte blocks allocated. */ -#ifdef __USE_MISC +#ifdef __USE_XOPEN2K8      /* Nanosecond resolution timestamps are stored in a format         equivalent to 'struct timespec'.  This is the type used         whenever possible but the Unix namespace rules do not allow the On 06/07/2020 15:40, Ed W wrote: