Re: lib/dirfd.c: compiler warning: unused parameter

[Bjarni Ingi Gislason]

On Thu, May 04, 2023 at 04:24:30AM +0200, Bruno Haible wrote:
> Bjarni,
> 
> Paul Eggert wrote:
> > Please look into config.log for that.
> 
> To make things clear and quick for us, please attach the generated files
>   - config.status,
>   - config.log.
> 
> Bruno
> 
> 
> 
  "GNULIB_defined_DIR" and "__KLIBC__" are not defined.

config.log:DIR_HAS_FD_MEMBER='1'
config.status:S["DIR_HAS_FD_MEMBER"]="1"

  "DIR_FD_MEMBER_NAME" first defined as "d_fd" then as "dd_fd".

  There is no "rpl_dirfd" mentioned in 'config*' files

"grep -F 'rpl_' config*" shows:

config.log:gl_cv_rpl_alloca='yes'
configure.lineno:if test ${gl_cv_rpl_alloca+y}
configure.lineno:  gl_cv_rpl_alloca=yes
configure.lineno:  e) gl_cv_rpl_alloca=no ;;
configure.lineno:{ printf "%s\n" "$as_me:${as_lineno-25914}: result: 
$gl_cv_rpl_alloca" >&5
configure.lineno:printf "%s\n" "$gl_cv_rpl_alloca" >&6; }
configure.lineno:    if test $gl_cv_rpl_alloca = yes; then
configure.lineno:/* malloc might have been renamed as rpl_malloc. */


  Lines in config.out.latest:

checking for dirfd... yes
checking whether dirfd is declared... yes
checking whether dirfd is a macro... no
checking how to get the file descriptor associated with an open DIR*...
no_such_member
checking whether // is distinct from /... no


  Lines in config.log concerning "dirfd":

configure:26555: checking for dirfd
configure:26555: /usr/bin/gcc-12 -o conftest -Walloc-zero -Walloca -Wall 
-Wextra -Wformat=2 -Wattribute-warning -Wdate-time -Wformat-security 
-Wfree-nonheap-object -Wimplicit-fallthrough=3 -Wmissing-noreturn -Wpedantic 
-Wstringop-overflow=4 -Wredundant-decls -Wshadow=global 
-Wsuggest-attribute=noreturn -Wuninitialized -Wunused -Wunused-parameter -Wvla 
-fdiagnostics-generate-patch -freport-bug -fsanitize=undefined -fsanitize=bool 
-fsanitize=enum -fsanitize=signed-integer-overflow 
-fsanitize=integer-divide-by-zero,shift,null -fsanitize-undefined-trap-on-error 
-fno-sanitize=pointer-overflow -fsanitize=return 
-fsanitize=alignment,object-size,vptr,pointer-overflow -O2 
-fstack-protector-strong -fno-common -fstack-clash-protection -ftrapv 
-funsigned-char -fvar-tracking-assignments -ggdb3 -fsanitize=null 
-fsanitize=nonnull-attribute  -Wbad-function-cast -Wmissing-prototypes 
-Wold-style-definition -Wstrict-prototypes  -Wold-style-declaration  -std=gnu2x 
 -D_FORTIFY_SOURCE=2 -DGCC_LINT -DGNULIB_NO_VLA -D__USE_ISOC11   conftest.c  >&5
configure:26555: $? = 0
configure:26555: result: yes
configure:26562: checking whether dirfd is declared
configure:26562: /usr/bin/gcc-12 -c -Walloc-zero -Walloca -Wall -Wextra 
-Wformat=2 -Wattribute-warning -Wdate-time -Wformat-security 
-Wfree-nonheap-object -Wimplicit-fallthrough=3 -Wmissing-noreturn -Wpedantic 
-Wstringop-overflow=4 -Wredundant-decls -Wshadow=global 
-Wsuggest-attribute=noreturn -Wuninitialized -Wunused -Wunused-parameter -Wvla 
-fdiagnostics-generate-patch -freport-bug -fsanitize=undefined -fsanitize=bool 
-fsanitize=enum -fsanitize=signed-integer-overflow 
-fsanitize=integer-divide-by-zero,shift,null -fsanitize-undefined-trap-on-error 
-fno-sanitize=pointer-overflow -fsanitize=return 
-fsanitize=alignment,object-size,vptr,pointer-overflow -O2 
-fstack-protector-strong -fno-common -fstack-clash-protection -ftrapv 
-funsigned-char -fvar-tracking-assignments -ggdb3 -fsanitize=null 
-fsanitize=nonnull-attribute  -Wbad-function-cast -Wmissing-prototypes 
-Wold-style-definition -Wstrict-prototypes  -Wold-style-declaration  -std=gnu2x 
  -D_FORTIFY_SOURCE=2 -DGCC_LINT -DGNULIB_NO_VLA -D__USE_ISOC11  conftest.c >&5
configure:26562: $? = 0
configure:26562: result: yes
configure:26578: checking whether dirfd is a macro
configure:26605: result: no
configure:26641: checking how to get the file descriptor associated with an 
open DIR*
configure:26665: /usr/bin/gcc-12 -c -Walloc-zero -Walloca -Wall -Wextra 
-Wformat=2 -Wattribute-warning -Wdate-time -Wformat-security 
-Wfree-nonheap-object -Wimplicit-fallthrough=3 -Wmissing-noreturn -Wpedantic 
-Wstringop-overflow=4 -Wredundant-decls -Wshadow=global 
-Wsuggest-attribute=noreturn -Wuninitialized -Wunused -Wunused-parameter -Wvla 
-fdiagnostics-generate-patch -freport-bug -fsanitize=undefined -fsanitize=bool 
-fsanitize=enum -fsanitize=signed-integer-overflow 
-fsanitize=integer-divide-by-zero,shift,null -fsanitize-undefined-trap-on-error 
-fno-sanitize=pointer-overflow -fsanitize=return 
-fsanitize=alignment,object-size,vptr,pointer-overflow -O2 
-fstack-protector-strong -fno-common -fstack-clash-protection -ftrapv 
-funsigned-char -fvar-tracking-assignments -ggdb3 -fsanitize=null 
-fsanitize=nonnull-attribute  -Wbad-function-cast -Wmissing-prototypes 
-Wold-style-definition -Wstrict-prototypes  -Wold-style-declaration  -std=gnu2x 
 -DDIR_FD_MEMBER_NAME=d_fd -D_FORTIFY_SOURCE=2 -DGCC_LINT -DGNULIB_NO_VLA 
-D__USE_ISOC11  conftest.c >&5
conftest.c: In function 'main':
conftest.c:156:40: error: invalid use of incomplete typedef 'DIR'
  156 | DIR *dir_p = opendir("."); (void) dir_p->DIR_FD_MEMBER_NAME;
      |                                        ^~
configure:26665: $? = 1
configure: failed program was:
| /* confdefs.h */
| #define PACKAGE_NAME "GNU roff"
| #define PACKAGE_TARNAME "groff"
| #define PACKAGE_VERSION "1.22.4.6592-03110"
| #define PACKAGE_STRING "GNU roff 1.22.4.6592-03110"
| #define PACKAGE_BUGREPORT "http://savannah.gnu.org/bugs/?group=groff";
| #define PACKAGE_URL "https://www.gnu.org/software/groff/";
| #define HAVE_STDIO_H 1
| #define HAVE_STDLIB_H 1
| #define HAVE_STRING_H 1
| #define HAVE_INTTYPES_H 1
| #define HAVE_STDINT_H 1
| #define HAVE_STRINGS_H 1
| #define HAVE_SYS_STAT_H 1
| #define HAVE_SYS_TYPES_H 1
| #define HAVE_UNISTD_H 1
| #define HAVE_WCHAR_H 1
| #define HAVE_SYS_PARAM_H 1
| #define HAVE_SYS_SOCKET_H 1
| #define HAVE_DIRENT_H 1
| #define HAVE_ERROR_H 1
| #define HAVE_FEATURES_H 1
| #define HAVE_LIMITS_H 1
| #define HAVE_LANGINFO_H 1
| #define HAVE_THREADS_H 1
| #define HAVE_MATH_H 1
| #define HAVE_SYS_MMAN_H 1
| #define HAVE_SYS_TIME_H 1
| #define HAVE_STDBOOL_H 1
| #define HAVE_SYS_RANDOM_H 1
| #define HAVE_WCTYPE_H 1
| #define STDC_HEADERS 1
| #define _ALL_SOURCE 1
| #define _DARWIN_C_SOURCE 1
| #define _GNU_SOURCE 1
| #define _HPUX_ALT_XOPEN_SOCKET_API 1
| #define _NETBSD_SOURCE 1
| #define _OPENBSD_SOURCE 1
| #define _POSIX_PTHREAD_SEMANTICS 1
| #define __STDC_WANT_IEC_60559_ATTRIBS_EXT__ 1
| #define __STDC_WANT_IEC_60559_BFP_EXT__ 1
| #define __STDC_WANT_IEC_60559_DFP_EXT__ 1
| #define __STDC_WANT_IEC_60559_EXT__ 1
| #define __STDC_WANT_IEC_60559_FUNCS_EXT__ 1
| #define __STDC_WANT_IEC_60559_TYPES_EXT__ 1
| #define __STDC_WANT_LIB_EXT2__ 1
| #define __STDC_WANT_MATH_SPEC_FUNCS__ 1
| #define _TANDEM_SOURCE 1
| #define __EXTENSIONS__ 1
| #define PACKAGE "groff"
| #define VERSION "1.22.4.6592-03110"
| #define __USE_MINGW_ANSI_STDIO 1
| #define HAVE_ALLOCA_H 1
| #define HAVE_ALLOCA 1
| #define HAVE_FCHDIR 1
| #define HAVE_FCNTL 1
| #define HAVE_SYMLINK 1
| #define HAVE_FDOPENDIR 1
| #define HAVE_SNPRINTF 1
| #define HAVE_FSTATAT 1
| #define HAVE_GETDTABLESIZE 1
| #define HAVE_LSTAT 1
| #define HAVE_MPROTECT 1
| #define HAVE_MKSTEMP 1
| #define HAVE_OPENAT 1
| #define HAVE_PIPE 1
| #define HAVE_ISWCNTRL 1
| #define HAVE_WCWIDTH 1
| #define HAVE_GETPAGESIZE 1
| #define HAVE_ENVIRON_DECL 1
| #define HAVE_ERROR 1
| #define HAVE_DECL_STRERROR_R 1
| #define HAVE_STRERROR_R 1
| #define STRERROR_R_CHAR_P 1
| #define HAVE_DECL_FCHDIR 1
| #define HAVE_WORKING_O_NOATIME 1
| #define HAVE_WORKING_O_NOFOLLOW 1
| #define HAVE_DECL_ALARM 1
| #define HAVE_FREXP 1
| #define HAVE_DECL_TRUNC 1
| #define HAVE_STDINT_H_WITH_UINTMAX 1
| #define HAVE_INTTYPES_H_WITH_UINTMAX 1
| #define CHECK_PRINTF_SAFE 1
| #define HAVE_WCHAR_T 1
| #define HAVE_WINT_T 1
| #define DBL_EXPBIT0_WORD 1
| #define DBL_EXPBIT0_BIT 20
| #define HAVE_WCSLEN 1
| #define HAVE_SNPRINTF 1
| #define HAVE_STRNLEN 1
| #define HAVE_WCRTOMB 1
| #define HAVE_DECL__SNPRINTF 0
| #define HAVE_SNPRINTF_RETVAL_C99 1
| #define HAVE_SNPRINTF_TRUNCATION_C99 1
| #define HAVE_INTMAX_T 1
| #define restrict __restrict__
| #define LSTAT_FOLLOWS_SLASHED_SYMLINK 1
| #define HAVE_DECL_GETCWD 1
| #define HAVE_DECL_GETDTABLESIZE 1
| #define HAVE_LONG_LONG_INT 1
| #define HAVE_UNSIGNED_LONG_LONG_INT 1
| #define FLT_EXPBIT0_WORD 0
| #define FLT_EXPBIT0_BIT 23
| #define LDBL_EXPBIT0_WORD 2
| #define LDBL_EXPBIT0_BIT 0
| #define HAVE_LANGINFO_CODESET 1
| #define HAVE_LC_MESSAGES 1
| #define HAVE_USELOCALE 1
| #define HAVE_WORKING_USELOCALE 1
| #define HAVE_GOOD_USELOCALE 1
| #define HAVE_WEAK_SYMBOLS 1
| #define HAVE_PTHREAD_API 1
| #define USE_POSIX_THREADS 1
| #define USE_POSIX_THREADS_FROM_LIBC 1
| #define HAVE_MALLOC_POSIX 1
| #define MALLOC_0_IS_NONNULL 1
| #define HAVE_MAP_ANONYMOUS 1
| #define HAVE_DECL_MEMRCHR 1
| #define HAVE_MINMAX_IN_SYS_PARAM_H 1
| #define PROMOTED_MODE_T mode_t
| #define SETLOCALE_NULL_ALL_MTSAFE 1
| #define SETLOCALE_NULL_ONE_MTSAFE 1
| #define HAVE_DECL_SNPRINTF 1
| #define HAVE_DECL_FCLOSEALL 1
| #define HAVE_DECL_GETW 1
| #define HAVE_DECL_PUTW 1
| #define HAVE_DECL_ECVT 1
| #define HAVE_DECL_FCVT 1
| #define HAVE_DECL_GCVT 1
| #define HAVE_DECL_STRDUP 1
| #define _USE_STD_STAT 1
| #define HAVE_DECL_EXECVPE 1
| #define HAVE_DECL_VSNPRINTF 1
| #define HAVE_VSNPRINTF 1
| #define HAVE_DECL_WCSDUP 1
| #define HAVE_TOWLOWER 1
| #define HAVE_ALLOCA 1
| #define GNULIB_TEST_CHDIR 1
| #define HAVE_CLOCK_GETRES 1
| #define HAVE_CLOCK_GETTIME 1
| #define HAVE_CLOCK_SETTIME 1
| #define GNULIB_TEST_CLOEXEC 1
| #define GNULIB_TEST_CLOSE 1
| #define HAVE_CLOSEDIR 1
| #define GNULIB_TEST_CLOSEDIR 1
| #define D_INO_IN_DIRENT 1
| #define HAVE_DIRFD 1
| #define HAVE_DECL_DIRFD 1
| /* end confdefs.h.  */
| 
|            #include <sys/types.h>
|            #include <dirent.h>
| int
| main (void)
| {
| DIR *dir_p = opendir("."); (void) dir_p->DIR_FD_MEMBER_NAME;
|   ;
|   return 0;
| }
configure:26665: /usr/bin/gcc-12 -c -Walloc-zero -Walloca -Wall -Wextra 
-Wformat=2 -Wattribute-warning -Wdate-time -Wformat-security 
-Wfree-nonheap-object -Wimplicit-fallthrough=3 -Wmissing-noreturn -Wpedantic 
-Wstringop-overflow=4 -Wredundant-decls -Wshadow=global 
-Wsuggest-attribute=noreturn -Wuninitialized -Wunused -Wunused-parameter -Wvla 
-fdiagnostics-generate-patch -freport-bug -fsanitize=undefined -fsanitize=bool 
-fsanitize=enum -fsanitize=signed-integer-overflow 
-fsanitize=integer-divide-by-zero,shift,null -fsanitize-undefined-trap-on-error 
-fno-sanitize=pointer-overflow -fsanitize=return 
-fsanitize=alignment,object-size,vptr,pointer-overflow -O2 
-fstack-protector-strong -fno-common -fstack-clash-protection -ftrapv 
-funsigned-char -fvar-tracking-assignments -ggdb3 -fsanitize=null 
-fsanitize=nonnull-attribute  -Wbad-function-cast -Wmissing-prototypes 
-Wold-style-definition -Wstrict-prototypes  -Wold-style-declaration  -std=gnu2x 
 -DDIR_FD_MEMBER_NAME=dd_fd -D_FORTIFY_SOURCE=2 -DGCC_LINT -DGNULIB_NO_VLA 
-D__USE_ISOC11  conftest.c >&5
conftest.c: In function 'main':
conftest.c:156:40: error: invalid use of incomplete typedef 'DIR'
  156 | DIR *dir_p = opendir("."); (void) dir_p->DIR_FD_MEMBER_NAME;
      |                                        ^~
configure:26665: $? = 1
configure: failed program was:
| /* confdefs.h */
| #define PACKAGE_NAME "GNU roff"
| #define PACKAGE_TARNAME "groff"
| #define PACKAGE_VERSION "1.22.4.6592-03110"
| #define PACKAGE_STRING "GNU roff 1.22.4.6592-03110"
| #define PACKAGE_BUGREPORT "http://savannah.gnu.org/bugs/?group=groff";
| #define PACKAGE_URL "https://www.gnu.org/software/groff/";
| #define HAVE_STDIO_H 1
| #define HAVE_STDLIB_H 1
| #define HAVE_STRING_H 1
| #define HAVE_INTTYPES_H 1
| #define HAVE_STDINT_H 1
| #define HAVE_STRINGS_H 1
| #define HAVE_SYS_STAT_H 1
| #define HAVE_SYS_TYPES_H 1
| #define HAVE_UNISTD_H 1
| #define HAVE_WCHAR_H 1
| #define HAVE_SYS_PARAM_H 1
| #define HAVE_SYS_SOCKET_H 1
| #define HAVE_DIRENT_H 1
| #define HAVE_ERROR_H 1
| #define HAVE_FEATURES_H 1
| #define HAVE_LIMITS_H 1
| #define HAVE_LANGINFO_H 1
| #define HAVE_THREADS_H 1
| #define HAVE_MATH_H 1
| #define HAVE_SYS_MMAN_H 1
| #define HAVE_SYS_TIME_H 1
| #define HAVE_STDBOOL_H 1
| #define HAVE_SYS_RANDOM_H 1
| #define HAVE_WCTYPE_H 1
| #define STDC_HEADERS 1
| #define _ALL_SOURCE 1
| #define _DARWIN_C_SOURCE 1
| #define _GNU_SOURCE 1
| #define _HPUX_ALT_XOPEN_SOCKET_API 1
| #define _NETBSD_SOURCE 1
| #define _OPENBSD_SOURCE 1
| #define _POSIX_PTHREAD_SEMANTICS 1
| #define __STDC_WANT_IEC_60559_ATTRIBS_EXT__ 1
| #define __STDC_WANT_IEC_60559_BFP_EXT__ 1
| #define __STDC_WANT_IEC_60559_DFP_EXT__ 1
| #define __STDC_WANT_IEC_60559_EXT__ 1
| #define __STDC_WANT_IEC_60559_FUNCS_EXT__ 1
| #define __STDC_WANT_IEC_60559_TYPES_EXT__ 1
| #define __STDC_WANT_LIB_EXT2__ 1
| #define __STDC_WANT_MATH_SPEC_FUNCS__ 1
| #define _TANDEM_SOURCE 1
| #define __EXTENSIONS__ 1
| #define PACKAGE "groff"
| #define VERSION "1.22.4.6592-03110"
| #define __USE_MINGW_ANSI_STDIO 1
| #define HAVE_ALLOCA_H 1
| #define HAVE_ALLOCA 1
| #define HAVE_FCHDIR 1
| #define HAVE_FCNTL 1
| #define HAVE_SYMLINK 1
| #define HAVE_FDOPENDIR 1
| #define HAVE_SNPRINTF 1
| #define HAVE_FSTATAT 1
| #define HAVE_GETDTABLESIZE 1
| #define HAVE_LSTAT 1
| #define HAVE_MPROTECT 1
| #define HAVE_MKSTEMP 1
| #define HAVE_OPENAT 1
| #define HAVE_PIPE 1
| #define HAVE_ISWCNTRL 1
| #define HAVE_WCWIDTH 1
| #define HAVE_GETPAGESIZE 1
| #define HAVE_ENVIRON_DECL 1
| #define HAVE_ERROR 1
| #define HAVE_DECL_STRERROR_R 1
| #define HAVE_STRERROR_R 1
| #define STRERROR_R_CHAR_P 1
| #define HAVE_DECL_FCHDIR 1
| #define HAVE_WORKING_O_NOATIME 1
| #define HAVE_WORKING_O_NOFOLLOW 1
| #define HAVE_DECL_ALARM 1
| #define HAVE_FREXP 1
| #define HAVE_DECL_TRUNC 1
| #define HAVE_STDINT_H_WITH_UINTMAX 1
| #define HAVE_INTTYPES_H_WITH_UINTMAX 1
| #define CHECK_PRINTF_SAFE 1
| #define HAVE_WCHAR_T 1
| #define HAVE_WINT_T 1
| #define DBL_EXPBIT0_WORD 1
| #define DBL_EXPBIT0_BIT 20
| #define HAVE_WCSLEN 1
| #define HAVE_SNPRINTF 1
| #define HAVE_STRNLEN 1
| #define HAVE_WCRTOMB 1
| #define HAVE_DECL__SNPRINTF 0
| #define HAVE_SNPRINTF_RETVAL_C99 1
| #define HAVE_SNPRINTF_TRUNCATION_C99 1
| #define HAVE_INTMAX_T 1
| #define restrict __restrict__
| #define LSTAT_FOLLOWS_SLASHED_SYMLINK 1
| #define HAVE_DECL_GETCWD 1
| #define HAVE_DECL_GETDTABLESIZE 1
| #define HAVE_LONG_LONG_INT 1
| #define HAVE_UNSIGNED_LONG_LONG_INT 1
| #define FLT_EXPBIT0_WORD 0
| #define FLT_EXPBIT0_BIT 23
| #define LDBL_EXPBIT0_WORD 2
| #define LDBL_EXPBIT0_BIT 0
| #define HAVE_LANGINFO_CODESET 1
| #define HAVE_LC_MESSAGES 1
| #define HAVE_USELOCALE 1
| #define HAVE_WORKING_USELOCALE 1
| #define HAVE_GOOD_USELOCALE 1
| #define HAVE_WEAK_SYMBOLS 1
| #define HAVE_PTHREAD_API 1
| #define USE_POSIX_THREADS 1
| #define USE_POSIX_THREADS_FROM_LIBC 1
| #define HAVE_MALLOC_POSIX 1
| #define MALLOC_0_IS_NONNULL 1
| #define HAVE_MAP_ANONYMOUS 1
| #define HAVE_DECL_MEMRCHR 1
| #define HAVE_MINMAX_IN_SYS_PARAM_H 1
| #define PROMOTED_MODE_T mode_t
| #define SETLOCALE_NULL_ALL_MTSAFE 1
| #define SETLOCALE_NULL_ONE_MTSAFE 1
| #define HAVE_DECL_SNPRINTF 1
| #define HAVE_DECL_FCLOSEALL 1
| #define HAVE_DECL_GETW 1
| #define HAVE_DECL_PUTW 1
| #define HAVE_DECL_ECVT 1
| #define HAVE_DECL_FCVT 1
| #define HAVE_DECL_GCVT 1
| #define HAVE_DECL_STRDUP 1
| #define _USE_STD_STAT 1
| #define HAVE_DECL_EXECVPE 1
| #define HAVE_DECL_VSNPRINTF 1
| #define HAVE_VSNPRINTF 1
| #define HAVE_DECL_WCSDUP 1
| #define HAVE_TOWLOWER 1
| #define HAVE_ALLOCA 1
| #define GNULIB_TEST_CHDIR 1
| #define HAVE_CLOCK_GETRES 1
| #define HAVE_CLOCK_GETTIME 1
| #define HAVE_CLOCK_SETTIME 1
| #define GNULIB_TEST_CLOEXEC 1
| #define GNULIB_TEST_CLOSE 1
| #define HAVE_CLOSEDIR 1
| #define GNULIB_TEST_CLOSEDIR 1
| #define D_INO_IN_DIRENT 1
| #define HAVE_DIRFD 1
| #define HAVE_DECL_DIRFD 1
| /* end confdefs.h.  */
| 
|            #include <sys/types.h>
|            #include <dirent.h>
| int
| main (void)
| {
| DIR *dir_p = opendir("."); (void) dir_p->DIR_FD_MEMBER_NAME;
|   ;
|   return 0;
| }
configure:26681: result: no_such_member
configure:26713: checking whether // is distinct from /
configure:26744: result: no
configure:26772: checking whether dup works
[...]

config.status
Description: Text document

config.log
Description: Text document