[08/11] configure: Use -Wno-ignored-attributes if compiler warns about multiple aliases

Message ID 20221028173532.876027-9-adhemerval.zanella@linaro.org
State Superseded
Headers
Series Initial fixes for clang build support |

Checks

Context Check Description
dj/TryBot-apply_patch success Patch applied to master at the time it was sent

Commit Message

Adhemerval Zanella Oct. 28, 2022, 5:35 p.m. UTC
  clang emits an warning when a double alias redirection is used, to warn
the the original symbol will be used even when weak definition is
overridden.  Howerver, this is a common pattern for weak_alias, where
multiple alias are set to same symbol.
---
 argp/Makefile                |  7 ++++---
 configure                    | 29 +++++++++++++++++++++++++++++
 configure.ac                 | 22 ++++++++++++++++++++++
 dirent/Makefile              |  1 +
 inet/Makefile                |  3 +++
 io/Makefile                  | 18 ++++++++++--------
 libio/Makefile               | 14 +++++++++++---
 login/Makefile               |  1 +
 misc/Makefile                |  2 ++
 posix/Makefile               |  6 +++---
 resolv/Makefile              |  1 +
 resource/Makefile            |  3 +++
 socket/Makefile              | 10 +++++-----
 stdio-common/Makefile        |  2 ++
 stdlib/Makefile              | 12 ++++++++++++
 string/Makefile              |  9 +++++++++
 sysdeps/aarch64/Makefile     |  1 +
 sysdeps/arm/Makefile         |  4 ++++
 sysdeps/wordsize-64/Makefile |  5 +++++
 termios/Makefile             |  1 +
 time/Makefile                |  1 +
 wcsmbs/Makefile              | 24 ++++++++++++++++--------
 wctype/Makefile              |  2 ++
 23 files changed, 148 insertions(+), 30 deletions(-)
  

Comments

Fangrui Song Oct. 29, 2022, 5:59 a.m. UTC | #1
On 2022-10-28, Adhemerval Zanella via Libc-alpha wrote:
>clang emits an warning when a double alias redirection is used, to warn
>the the original symbol will be used even when weak definition is
>overridden.  Howerver, this is a common pattern for weak_alias, where
>multiple alias are set to same symbol.

Confirmed that the pattern is common.  

% rg -U 'libc_hidden_def.*\nweak_alias.*\nlibc_hidden_weak' -l
login/getlogin_r.c
libio/iofgets_u.c
libio/iofflush.c
libio/iofputs_u.c
libio/iofflush_u.c
libio/iofgets.c
libio/fileno.c
string/memmem.c
resource/getrlimit64.c
string/argz-next.c
inet/if_index.c
io/open.c
string/basename.c
wcsmbs/wmemset.c
wcsmbs/wcschr.c
wcsmbs/wmemchr.c
wctype/wcfuncs.c
resolv/inet_pton.c
sysdeps/x86_64/wmemchr.S
sysdeps/x86_64/memset.S
sysdeps/unix/getlogin_r.c
sysdeps/x86_64/wcschr.S
sysdeps/mach/hurd/getpid.c
sysdeps/mach/hurd/read.c
sysdeps/mach/hurd/write.c
sysdeps/mach/hurd/getlogin_r.c
sysdeps/mach/hurd/if_index.c
sysdeps/mach/hurd/fcntl.c
sysdeps/mach/hurd/open.c
sysdeps/unix/sysv/linux/getlogin_r.c
sysdeps/unix/sysv/linux/fcntl64.c
sysdeps/unix/sysv/linux/if_index.c

The three macros can be reordered and there may be more results.

I just took some notes here https://maskray.me/blog/2021-10-10-when-can-glibc-be-built-with-clang#alias-to-a-weak-alias
I feel that the pattern is ugly but I cannot figure out a better way. Clang has a reasonable diagnostic. It is fine to 
ignore it as the Clang symbol codegen matches GCC.

```
26: 0000000000000000   596 FUNC    GLOBAL HIDDEN     1 __GI___mbrtowc
33: 0000000000000000   596 FUNC    GLOBAL DEFAULT    1 __mbrtowc
34: 0000000000000000   596 FUNC    WEAK   HIDDEN     1 __GI_mbrtowc
35: 0000000000000000   596 FUNC    WEAK   DEFAULT    1 mbrtowc
```

So here is a Reviewed-by tag: but I really hope that we can come up with a better way.

Reviewed-by: Fangrui Song <maskray@google.com>
  
Adhemerval Zanella Oct. 31, 2022, 7:59 p.m. UTC | #2
On 29/10/22 02:59, Fangrui Song wrote:
> On 2022-10-28, Adhemerval Zanella via Libc-alpha wrote:
>> clang emits an warning when a double alias redirection is used, to warn
>> the the original symbol will be used even when weak definition is
>> overridden.  Howerver, this is a common pattern for weak_alias, where
>> multiple alias are set to same symbol.
> 
> Confirmed that the pattern is common. 
> % rg -U 'libc_hidden_def.*\nweak_alias.*\nlibc_hidden_weak' -l
> login/getlogin_r.c
> libio/iofgets_u.c
> libio/iofflush.c
> libio/iofputs_u.c
> libio/iofflush_u.c
> libio/iofgets.c
> libio/fileno.c
> string/memmem.c
> resource/getrlimit64.c
> string/argz-next.c
> inet/if_index.c
> io/open.c
> string/basename.c
> wcsmbs/wmemset.c
> wcsmbs/wcschr.c
> wcsmbs/wmemchr.c
> wctype/wcfuncs.c
> resolv/inet_pton.c
> sysdeps/x86_64/wmemchr.S
> sysdeps/x86_64/memset.S
> sysdeps/unix/getlogin_r.c
> sysdeps/x86_64/wcschr.S
> sysdeps/mach/hurd/getpid.c
> sysdeps/mach/hurd/read.c
> sysdeps/mach/hurd/write.c
> sysdeps/mach/hurd/getlogin_r.c
> sysdeps/mach/hurd/if_index.c
> sysdeps/mach/hurd/fcntl.c
> sysdeps/mach/hurd/open.c
> sysdeps/unix/sysv/linux/getlogin_r.c
> sysdeps/unix/sysv/linux/fcntl64.c
> sysdeps/unix/sysv/linux/if_index.c
> 
> The three macros can be reordered and there may be more results.

Yes, I added as per need for the ABIs I am working now (aarch64, x86_64, i686,
and armhf).  It would most likely need to add such warning suppression when/if
more architecture are enabled.

> 
> I just took some notes here https://maskray.me/blog/2021-10-10-when-can-glibc-be-built-with-clang#alias-to-a-weak-alias
> I feel that the pattern is ugly but I cannot figure out a better way. Clang has a reasonable diagnostic. It is fine to ignore it as the Clang symbol codegen matches GCC.
> 
> ```
> 26: 0000000000000000   596 FUNC    GLOBAL HIDDEN     1 __GI___mbrtowc
> 33: 0000000000000000   596 FUNC    GLOBAL DEFAULT    1 __mbrtowc
> 34: 0000000000000000   596 FUNC    WEAK   HIDDEN     1 __GI_mbrtowc
> 35: 0000000000000000   596 FUNC    WEAK   DEFAULT    1 mbrtowc
> ```
> 
> So here is a Reviewed-by tag: but I really hope that we can come up with a better way.

I am open to how to better solve as well, I might revise it in the future.

> 
> Reviewed-by: Fangrui Song <maskray@google.com>

Thanks.
  
Fangrui Song Oct. 31, 2022, 8:11 p.m. UTC | #3
On 2022-10-31, Adhemerval Zanella Netto wrote:
>
>
>On 29/10/22 02:59, Fangrui Song wrote:
>> On 2022-10-28, Adhemerval Zanella via Libc-alpha wrote:
>>> clang emits an warning when a double alias redirection is used, to warn
>>> the the original symbol will be used even when weak definition is
>>> overridden.  Howerver, this is a common pattern for weak_alias, where
>>> multiple alias are set to same symbol.
>>
>> Confirmed that the pattern is common. 
>> % rg -U 'libc_hidden_def.*\nweak_alias.*\nlibc_hidden_weak' -l
>> login/getlogin_r.c
>> libio/iofgets_u.c
>> libio/iofflush.c
>> libio/iofputs_u.c
>> libio/iofflush_u.c
>> libio/iofgets.c
>> libio/fileno.c
>> string/memmem.c
>> resource/getrlimit64.c
>> string/argz-next.c
>> inet/if_index.c
>> io/open.c
>> string/basename.c
>> wcsmbs/wmemset.c
>> wcsmbs/wcschr.c
>> wcsmbs/wmemchr.c
>> wctype/wcfuncs.c
>> resolv/inet_pton.c
>> sysdeps/x86_64/wmemchr.S
>> sysdeps/x86_64/memset.S
>> sysdeps/unix/getlogin_r.c
>> sysdeps/x86_64/wcschr.S
>> sysdeps/mach/hurd/getpid.c
>> sysdeps/mach/hurd/read.c
>> sysdeps/mach/hurd/write.c
>> sysdeps/mach/hurd/getlogin_r.c
>> sysdeps/mach/hurd/if_index.c
>> sysdeps/mach/hurd/fcntl.c
>> sysdeps/mach/hurd/open.c
>> sysdeps/unix/sysv/linux/getlogin_r.c
>> sysdeps/unix/sysv/linux/fcntl64.c
>> sysdeps/unix/sysv/linux/if_index.c
>>
>> The three macros can be reordered and there may be more results.
>
>Yes, I added as per need for the ABIs I am working now (aarch64, x86_64, i686,
>and armhf).  It would most likely need to add such warning suppression when/if
>more architecture are enabled.
>
>>
>> I just took some notes here https://maskray.me/blog/2021-10-10-when-can-glibc-be-built-with-clang#alias-to-a-weak-alias
>> I feel that the pattern is ugly but I cannot figure out a better way. Clang has a reasonable diagnostic. It is fine to ignore it as the Clang symbol codegen matches GCC.
>>
>> ```
>> 26: 0000000000000000   596 FUNC    GLOBAL HIDDEN     1 __GI___mbrtowc
>> 33: 0000000000000000   596 FUNC    GLOBAL DEFAULT    1 __mbrtowc
>> 34: 0000000000000000   596 FUNC    WEAK   HIDDEN     1 __GI_mbrtowc
>> 35: 0000000000000000   596 FUNC    WEAK   DEFAULT    1 mbrtowc
>> ```
>>
>> So here is a Reviewed-by tag: but I really hope that we can come up with a better way.
>
>I am open to how to better solve as well, I might revise it in the future.

I think there is likely room for improvement but that can be very tricky (need to think how to reorganize the attributes and need to refactor at least the above files).
-Wno-ignored-attributes is a decent solution for now, so I provided a Reviewed-by: :)

>>
>> Reviewed-by: Fangrui Song <maskray@google.com>
>
>Thanks.
  

Patch

diff --git a/argp/Makefile b/argp/Makefile
index 586136f2fe..8de8fd6113 100644
--- a/argp/Makefile
+++ b/argp/Makefile
@@ -29,9 +29,10 @@  routines	= $(addprefix argp-, ba fmtstream fs-xinl help parse pv \
 tests		= argp-test tst-argp1 bug-argp1 tst-argp2 bug-argp2 \
 		  tst-ldbl-argp
 
-CFLAGS-argp-help.c += $(uses-callbacks) -fexceptions
-CFLAGS-argp-parse.c += $(uses-callbacks)
-CFLAGS-argp-fmtstream.c += -fexceptions
+CFLAGS-argp-help.c += $(uses-callbacks) -fexceptions $(config-cflags-wno-ignored-attributes)
+CFLAGS-argp-parse.c += $(uses-callbacks) $(config-cflags-wno-ignored-attributes)
+CFLAGS-argp-fmtstream.c += -fexceptions $(config-cflags-wno-ignored-attributes)
+CFLAGS-argp-fs-xinl.c += $(config-cflags-wno-ignored-attributes)
 
 bug-argp1-ARGS = -- --help
 bug-argp2-ARGS = -- -d 111 --dstaddr 222 -p 333 --peer 444
diff --git a/configure b/configure
index 1f5916af3f..939c3e094f 100755
--- a/configure
+++ b/configure
@@ -6257,6 +6257,35 @@  $as_echo "$libc_cv_mtls_dialect_gnu2" >&6; }
 config_vars="$config_vars
 have-mtls-dialect-gnu2 = $libc_cv_mtls_dialect_gnu2"
 
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking if -Wno-ignored-attributes is required for aliases" >&5
+$as_echo_n "checking if -Wno-ignored-attributes is required for aliases... " >&6; }
+if ${libc_cv_wno_ignored_attributes+:} false; then :
+  $as_echo_n "(cached) " >&6
+else
+  cat > conftest.c <<EOF
+void __foo (void)
+{
+}
+extern __typeof (__foo) foo __attribute__ ((weak, alias ("__foo")));
+extern __typeof (__foo) bar __attribute__ ((weak, alias ("foo")));
+EOF
+libc_cv_wno_ignored_attributes=""
+if ! { ac_try='${CC-cc} $CFLAGS $CPPFLAGS -Werror -c conftest.c'
+  { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_try\""; } >&5
+  (eval $ac_try) 2>&5
+  ac_status=$?
+  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+  test $ac_status = 0; }; }
+then
+  libc_cv_wno_ignored_attributes="-Wno-ignored-attributes"
+fi
+rm -f conftest*
+fi
+{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $libc_cv_wno_ignored_attributes" >&5
+$as_echo "$libc_cv_wno_ignored_attributes" >&6; }
+config_vars="$config_vars
+config-cflags-wno-ignored-attributes = $libc_cv_wno_ignored_attributes"
+
 { $as_echo "$as_me:${as_lineno-$LINENO}: checking whether cc puts quotes around section names" >&5
 $as_echo_n "checking whether cc puts quotes around section names... " >&6; }
 if ${libc_cv_have_section_quotes+:} false; then :
diff --git a/configure.ac b/configure.ac
index c207503c8a..98bd9c01f8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1403,6 +1403,28 @@  rm -f conftest*])
 AC_SUBST(libc_cv_mtls_dialect_gnu2)
 LIBC_CONFIG_VAR([have-mtls-dialect-gnu2], [$libc_cv_mtls_dialect_gnu2])
 
+dnl clang emits an warning when a double alias redirection is used, to warn
+dnl the the original symbol will be used even when weak definition is overridden.
+dnl This is a common pattern for weak_alias, where multiple alias are set to
+dnl same symbol.
+AC_CACHE_CHECK([if -Wno-ignored-attributes is required for aliases],
+	       libc_cv_wno_ignored_attributes, [dnl
+cat > conftest.c <<EOF
+void __foo (void)
+{
+}
+extern __typeof (__foo) foo __attribute__ ((weak, alias ("__foo")));
+extern __typeof (__foo) bar __attribute__ ((weak, alias ("foo")));
+EOF
+libc_cv_wno_ignored_attributes=""
+if ! AC_TRY_COMMAND([${CC-cc} $CFLAGS $CPPFLAGS -Werror -c conftest.c])
+then
+  libc_cv_wno_ignored_attributes="-Wno-ignored-attributes"
+fi
+rm -f conftest*])
+LIBC_CONFIG_VAR([config-cflags-wno-ignored-attributes],
+		[$libc_cv_wno_ignored_attributes])
+
 AC_CACHE_CHECK(whether cc puts quotes around section names,
 	       libc_cv_have_section_quotes,
 	       [cat > conftest.c <<EOF
diff --git a/dirent/Makefile b/dirent/Makefile
index b80f6a73ea..cfa61826ed 100644
--- a/dirent/Makefile
+++ b/dirent/Makefile
@@ -37,6 +37,7 @@  CFLAGS-scandir.c += $(uses-callbacks)
 CFLAGS-scandir64.c += $(uses-callbacks)
 CFLAGS-scandir-tail.c += $(uses-callbacks)
 CFLAGS-scandir64-tail.c += $(uses-callbacks)
+CFLAGS-dirfd.c += $(config-cflags-wno-ignored-attributes)
 
 include ../Rules
 
diff --git a/inet/Makefile b/inet/Makefile
index 9b96e57cac..a5ef1ec0a3 100644
--- a/inet/Makefile
+++ b/inet/Makefile
@@ -106,6 +106,9 @@  CFLAGS-either_ntoh.c += -fexceptions
 CFLAGS-either_hton.c += -fexceptions
 CFLAGS-getnetgrent.c += -fexceptions
 CFLAGS-getnetgrent_r.c += -fexceptions
+CFLAGS-in6_addr.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-if_index.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-ifaddrs.c += $(config-cflags-wno-ignored-attributes)
 
 CFLAGS-tst-checks-posix.c += -std=c99
 CFLAGS-tst-sockaddr.c += -fno-strict-aliasing
diff --git a/io/Makefile b/io/Makefile
index b1710407d0..14329e58fe 100644
--- a/io/Makefile
+++ b/io/Makefile
@@ -107,20 +107,21 @@  endif
 
 include ../Rules
 
-CFLAGS-open.c += -fexceptions -fasynchronous-unwind-tables
+CFLAGS-open.c += -fexceptions -fasynchronous-unwind-tables $(config-cflags-wno-ignored-attributes)
+CFLAGS-openat.c += $(config-cflags-wno-ignored-attributes)
 CFLAGS-open64.c += -fexceptions -fasynchronous-unwind-tables
 CFLAGS-creat.c += -fexceptions -fasynchronous-unwind-tables
 CFLAGS-creat64.c += -fexceptions -fasynchronous-unwind-tables
-CFLAGS-fcntl.c += -fexceptions -fasynchronous-unwind-tables
-CFLAGS-fcntl64.c += -fexceptions -fasynchronous-unwind-tables
+CFLAGS-fcntl.c += -fexceptions -fasynchronous-unwind-tables $(config-cflags-wno-ignored-attributes)
+CFLAGS-fcntl64.c += -fexceptions -fasynchronous-unwind-tables $(config-cflags-wno-ignored-attributes)
 CFLAGS-poll.c += -fexceptions -fasynchronous-unwind-tables
 CFLAGS-ppoll.c += -fexceptions -fasynchronous-unwind-tables
 CFLAGS-lockf.c += -fexceptions -fasynchronous-unwind-tables
-CFLAGS-lockf64.c += -fexceptions -fasynchronous-unwind-tables
+CFLAGS-lockf64.c += -fexceptions -fasynchronous-unwind-tables $(config-cflags-wno-ignored-attributes)
 CFLAGS-statfs.c += -fexceptions
 CFLAGS-fstatfs.c += -fexceptions
-CFLAGS-statvfs.c += -fexceptions
-CFLAGS-fstatvfs.c += -fexceptions
+CFLAGS-statvfs.c += -fexceptions $(config-cflags-wno-ignored-attributes)
+CFLAGS-fstatvfs.c += -fexceptions $(config-cflags-wno-ignored-attributes)
 CFLAGS-fts.c += -Wno-uninitialized $(uses-callbacks) -fexceptions
 CFLAGS-fts64.c += -Wno-uninitialized $(uses-callbacks) -fexceptions
 CFLAGS-fts64-time64.c += -Wno-uninitialized $(uses-callbacks) -fexceptions
@@ -131,9 +132,10 @@  CFLAGS-posix_fallocate.c += -fexceptions
 CFLAGS-posix_fallocate64.c += -fexceptions
 CFLAGS-fallocate.c += -fexceptions
 CFLAGS-fallocate64.c += -fexceptions
-CFLAGS-read.c += -fexceptions -fasynchronous-unwind-tables
-CFLAGS-write.c += -fexceptions -fasynchronous-unwind-tables
+CFLAGS-read.c += -fexceptions -fasynchronous-unwind-tables $(config-cflags-wno-ignored-attributes)
+CFLAGS-write.c += -fexceptions -fasynchronous-unwind-tables $(config-cflags-wno-ignored-attributes)
 CFLAGS-close.c += -fexceptions -fasynchronous-unwind-tables
+CFLAGS-lseek64.c += $(config-cflags-wno-ignored-attributes)
 
 CFLAGS-test-stat.c += -D_FILE_OFFSET_BITS=64 -D_LARGEFILE64_SOURCE
 CFLAGS-test-lfs.c += -D_LARGEFILE64_SOURCE
diff --git a/libio/Makefile b/libio/Makefile
index 3a02611020..64398ab1ee 100644
--- a/libio/Makefile
+++ b/libio/Makefile
@@ -112,18 +112,18 @@  CFLAGS-getchar.c += -fexceptions
 CFLAGS-getwc.c += -fexceptions
 CFLAGS-getwchar.c += -fexceptions
 CFLAGS-iofclose.c += -fexceptions
-CFLAGS-iofflush.c += -fexceptions
+CFLAGS-iofflush.c += -fexceptions $(config-cflags-wno-ignored-attributes)
 CFLAGS-iofgetpos64.c += -fexceptions
 CFLAGS-iofgetpos.c += -fexceptions
 CFLAGS-iofgets.c += -fexceptions
 CFLAGS-iofgetws.c += -fexceptions
-CFLAGS-iofputs.c += -fexceptions
+CFLAGS-iofputs.c += -fexceptions $(config-cflags-wno-ignored-attributes)
 CFLAGS-iofputws.c += -fexceptions
 CFLAGS-iofread.c += -fexceptions
 CFLAGS-iofsetpos64.c += -fexceptions
 CFLAGS-iofsetpos.c += -fexceptions
 CFLAGS-ioftell.c += -fexceptions
-CFLAGS-iofwrite.c += -fexceptions
+CFLAGS-iofwrite.c += -fexceptions $(config-cflags-wno-ignored-attributes)
 CFLAGS-iogetdelim.c += -fexceptions
 CFLAGS-iogetline.c += -fexceptions
 CFLAGS-iogets.c += -fexceptions
@@ -153,6 +153,14 @@  CFLAGS-oldiofopen.c += -fexceptions
 CFLAGS-iofopen.c += -fexceptions
 CFLAGS-iofopen64.c += -fexceptions
 CFLAGS-oldtmpfile.c += -fexceptions
+CFLAGS-fileno.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-feof_u.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-ferror_u.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-getc_u.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-iofflush_u.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-putc_u.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-iofgets_u.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-iofputs_u.c += $(config-cflags-wno-ignored-attributes)
 # XXX Do we need filedoalloc and wfiledoalloc?  Others?
 
 CFLAGS-tst_putwc.c += -DOBJPFX=\"$(objpfx)\"
diff --git a/login/Makefile b/login/Makefile
index 62440499bc..a0a96f3bbe 100644
--- a/login/Makefile
+++ b/login/Makefile
@@ -64,6 +64,7 @@  endif # $(have-GLIBC_2.33)
 include ../Rules
 
 CFLAGS-getpt.c += -fexceptions
+CFLAGS-getlogin_r.c += $(config-cflags-wno-ignored-attributes)
 
 ifeq (yesyes,$(have-fpie)$(build-shared))
 pt_chown-cflags += $(pie-ccflag)
diff --git a/misc/Makefile b/misc/Makefile
index ba8232a0e9..014c601909 100644
--- a/misc/Makefile
+++ b/misc/Makefile
@@ -144,6 +144,8 @@  CFLAGS-tst-tsearch.c += $(stack-align-test-flags)
 CFLAGS-msync.c += -fexceptions -fasynchronous-unwind-tables
 CFLAGS-fdatasync.c += -fexceptions -fasynchronous-unwind-tables
 CFLAGS-fsync.c += -fexceptions -fasynchronous-unwind-tables
+CFLAGS-makedev.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-mmap64.c += $(config-cflags-wno-ignored-attributes)
 
 # Called during static library initialization, so turn stack-protection
 # off for non-shared builds.
diff --git a/posix/Makefile b/posix/Makefile
index d1df7c27cb..4d60449426 100644
--- a/posix/Makefile
+++ b/posix/Makefile
@@ -248,9 +248,9 @@  $(objpfx)config-name.h: $(..)scripts/config-uname.sh $(common-objpfx)config.make
 CFLAGS-getaddrinfo.c += -DRESOLVER -fexceptions
 CFLAGS-pause.c += -fexceptions -fasynchronous-unwind-tables
 CFLAGS-pread.c += -fexceptions -fasynchronous-unwind-tables
-CFLAGS-pread64.c += -fexceptions -fasynchronous-unwind-tables
+CFLAGS-pread64.c += -fexceptions -fasynchronous-unwind-tables $(config-cflags-wno-ignored-attributes)
 CFLAGS-pwrite.c += -fexceptions -fasynchronous-unwind-tables
-CFLAGS-pwrite64.c += -fexceptions -fasynchronous-unwind-tables
+CFLAGS-pwrite64.c += -fexceptions -fasynchronous-unwind-tables $(config-cflags-wno-ignored-attributes)
 CFLAGS-sleep.c += -fexceptions
 CFLAGS-wait.c += -fexceptions -fasynchronous-unwind-tables
 CFLAGS-waitid.c += -fexceptions -fasynchronous-unwind-tables
@@ -279,7 +279,7 @@  CFLAGS-execl.os = -fomit-frame-pointer
 CFLAGS-execvp.os = -fomit-frame-pointer
 CFLAGS-execlp.os = -fomit-frame-pointer
 CFLAGS-nanosleep.c += -fexceptions -fasynchronous-unwind-tables
-CFLAGS-fork.c = $(libio-mtsafe)
+CFLAGS-fork.c = $(libio-mtsafe) $(config-cflags-wno-ignored-attributes)
 
 tstgetopt-ARGS = -a -b -cfoobar --required foobar --optional=bazbug \
 		--none random --col --color --colour
diff --git a/resolv/Makefile b/resolv/Makefile
index f8a92c6cff..d9d887a0d0 100644
--- a/resolv/Makefile
+++ b/resolv/Makefile
@@ -234,6 +234,7 @@  LOCALES := en_US.UTF-8 en_US.ISO-8859-1
 include ../gen-locales.mk
 
 CFLAGS-res_hconf.c += -fexceptions
+CFLAGS-inet_pton.c += $(config-cflags-wno-ignored-attributes)
 
 # The DNS NSS modules needs the resolver.
 $(objpfx)libnss_dns.so: $(objpfx)libresolv.so
diff --git a/resource/Makefile b/resource/Makefile
index d3d230a538..a005eab3e5 100644
--- a/resource/Makefile
+++ b/resource/Makefile
@@ -28,3 +28,6 @@  routines := getrlimit setrlimit getrlimit64 setrlimit64 getrusage ulimit      \
 tests = tst-getrlimit bug-ulimit1
 
 include ../Rules
+
+CFLAGS-getrlimit64.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-getrlimit.c += $(config-cflags-wno-ignored-attributes)
diff --git a/socket/Makefile b/socket/Makefile
index 2bde78387f..bd659a5ad1 100644
--- a/socket/Makefile
+++ b/socket/Makefile
@@ -49,11 +49,11 @@  aux	 := sa_len
 
 include ../Rules
 
-CFLAGS-recv.c += -fexceptions -fasynchronous-unwind-tables
+CFLAGS-recv.c += -fexceptions -fasynchronous-unwind-tables $(config-cflags-wno-ignored-attributes)
 CFLAGS-recvfrom.c += -fexceptions -fasynchronous-unwind-tables
 CFLAGS-sendto.c += -fexceptions -fasynchronous-unwind-tables
 CFLAGS-recvmsg.c += -fexceptions -fasynchronous-unwind-tables
-CFLAGS-sendmsg.c += -fexceptions -fasynchronous-unwind-tables
-CFLAGS-send.c += -fexceptions -fasynchronous-unwind-tables
-CFLAGS-connect.c += -fexceptions -fasynchronous-unwind-tables
-CFLAGS-accept.c += -fexceptions -fasynchronous-unwind-tables
+CFLAGS-sendmsg.c += -fexceptions -fasynchronous-unwind-tables $(config-cflags-wno-ignored-attributes)
+CFLAGS-send.c += -fexceptions -fasynchronous-unwind-tables $(config-cflags-wno-ignored-attributes)
+CFLAGS-connect.c += -fexceptions -fasynchronous-unwind-tables $(config-cflags-wno-ignored-attributes)
+CFLAGS-accept.c += -fexceptions -fasynchronous-unwind-tables $(config-cflags-wno-ignored-attributes)
diff --git a/stdio-common/Makefile b/stdio-common/Makefile
index 9c98c02884..401dac69de 100644
--- a/stdio-common/Makefile
+++ b/stdio-common/Makefile
@@ -381,6 +381,8 @@  CFLAGS-isoc99_vscanf.c += -fexceptions
 CFLAGS-isoc99_fscanf.c += -fexceptions
 CFLAGS-isoc99_scanf.c += -fexceptions
 
+CFLAGS-dprintf.c += $(config-cflags-wno-ignored-attributes)
+
 # scanf14a.c and scanf16a.c test a deprecated extension which is no
 # longer visible under most conformance levels; see the source files
 # for more detail.
diff --git a/stdlib/Makefile b/stdlib/Makefile
index f7b25c1981..417d525d8e 100644
--- a/stdlib/Makefile
+++ b/stdlib/Makefile
@@ -375,6 +375,18 @@  CFLAGS-strfromd.c += $(libio-mtsafe)
 CFLAGS-strfromf.c += $(libio-mtsafe)
 CFLAGS-strfroml.c += $(libio-mtsafe)
 
+CFLAGS-strtol.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-strtoul.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-strtoll.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-strtoull.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-strtof.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-strtof_l.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-strtod.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-strtod_l.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-strtold.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-strtold_l.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-secure-getenv.c += $(config-cflags-wno-ignored-attributes)
+
 CFLAGS-tst-bsearch.c += $(stack-align-test-flags)
 CFLAGS-tst-qsort.c += $(stack-align-test-flags)
 CFLAGS-tst-makecontext.c += -funwind-tables
diff --git a/string/Makefile b/string/Makefile
index 641e062bbb..938f528b8d 100644
--- a/string/Makefile
+++ b/string/Makefile
@@ -231,6 +231,15 @@  LDFLAGS-tst-xbzero-opt = -z now
 CFLAGS-memcpy.c += $(no-stack-protector)
 CFLAGS-wordcopy.c += $(no-stack-protector)
 
+CFLAGS-argz-next.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-basename.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-ffs.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-memmem.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-memchr.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-mempcpy.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-stpcpy.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-strnlen.c += $(config-cflags-wno-ignored-attributes)
+
 ifeq ($(run-built-tests),yes)
 $(objpfx)tst-svc-cmp.out: tst-svc.expect $(objpfx)tst-svc.out
 	cmp $^ > $@; \
diff --git a/sysdeps/aarch64/Makefile b/sysdeps/aarch64/Makefile
index 17fb1c5b72..6a9559e5f5 100644
--- a/sysdeps/aarch64/Makefile
+++ b/sysdeps/aarch64/Makefile
@@ -57,6 +57,7 @@  endif
 
 ifeq ($(subdir),math)
 CPPFLAGS += -I../soft-fp
+CFLAGS-feupdateenv.c += $(config-cflags-wno-ignored-attributes)
 endif
 
 ifeq ($(subdir),misc)
diff --git a/sysdeps/arm/Makefile b/sysdeps/arm/Makefile
index da4226c8c8..d5cea717a9 100644
--- a/sysdeps/arm/Makefile
+++ b/sysdeps/arm/Makefile
@@ -54,6 +54,10 @@  ifeq ($(subdir),gmon)
 sysdep_routines += arm-mcount
 endif
 
+ifeq ($(subdir),math)
+CFLAGS-feupdateenv.c += $(config-cflags-wno-ignored-attributes)
+endif
+
 ifeq ($(subdir),rt)
 librt-sysdep_routines += rt-aeabi_unwind_cpp_pr1 rt-arm-unwind-resume
 librt-shared-only-routines += rt-aeabi_unwind_cpp_pr1 rt-arm-unwind-resume
diff --git a/sysdeps/wordsize-64/Makefile b/sysdeps/wordsize-64/Makefile
index 2fa934751f..db7764f664 100644
--- a/sysdeps/wordsize-64/Makefile
+++ b/sysdeps/wordsize-64/Makefile
@@ -1,3 +1,8 @@ 
 ifeq ($(subdir),misc)
 tests += tst-writev
 endif
+
+# strtol is aliased to stroll
+CFLAGS-strtol.c += -fno-builtin-strtoll $(config-cflags-wno-ignored-attributes)
+# strtoul is aliased to strtoull
+CFLAGS-strtoul.c += -fno-builtin-strtoull $(config-cflags-wno-ignored-attributes)
diff --git a/termios/Makefile b/termios/Makefile
index 54ed9fe51e..1490dd17b2 100644
--- a/termios/Makefile
+++ b/termios/Makefile
@@ -31,3 +31,4 @@  routines	:= speed cfsetspeed tcsetattr tcgetattr tcgetpgrp tcsetpgrp \
 include ../Rules
 
 CFLAGS-tcdrain.c += -fexceptions -fasynchronous-unwind-tables
+CFLAGS-tcsetattr.c += $(config-cflags-wno-ignored-attributes)
diff --git a/time/Makefile b/time/Makefile
index 470275b90c..dc6e2c93ad 100644
--- a/time/Makefile
+++ b/time/Makefile
@@ -98,6 +98,7 @@  CFLAGS-tzset.c += $(tz-cflags)
 CFLAGS-getdate.c += -fexceptions
 CFLAGS-clock_nanosleep.c += -fexceptions -fasynchronous-unwind-tables
 CFLAGS-nanosleep.c += -fexceptions -fasynchronous-unwind-tables
+CFLAGS-mktime.c += $(config-cflags-wno-ignored-attributes)
 
 # Don't warn about Y2k problem in strftime format string.
 CFLAGS-test_time.c += -Wno-format
diff --git a/wcsmbs/Makefile b/wcsmbs/Makefile
index 4af102a3f6..aaa067fc69 100644
--- a/wcsmbs/Makefile
+++ b/wcsmbs/Makefile
@@ -84,24 +84,32 @@  CFLAGS-wcwidth.c += -I../wctype
 CFLAGS-wcswidth.c += -I../wctype
 
 strtox-CFLAGS = -I../include
-CFLAGS-wcstol.c += $(strtox-CFLAGS)
-CFLAGS-wcstoul.c += $(strtox-CFLAGS)
+CFLAGS-wcstol.c += $(strtox-CFLAGS) $(config-cflags-wno-ignored-attributes)
+CFLAGS-wcstoul.c += $(strtox-CFLAGS) $(config-cflags-wno-ignored-attributes)
 CFLAGS-wcstoll.c += $(strtox-CFLAGS)
 CFLAGS-wcstoull.c += $(strtox-CFLAGS)
-CFLAGS-wcstod.c += $(strtox-CFLAGS)
-CFLAGS-wcstold.c += $(strtox-CFLAGS)
+CFLAGS-wcstod.c += $(strtox-CFLAGS) $(config-cflags-wno-ignored-attributes)
+CFLAGS-wcstold.c += $(strtox-CFLAGS) $(config-cflags-wno-ignored-attributes)
 CFLAGS-wcstof128.c += $(strtox-CFLAGS)
-CFLAGS-wcstof.c += $(strtox-CFLAGS)
+CFLAGS-wcstof.c += $(strtox-CFLAGS) $(config-cflags-wno-ignored-attributes)
 CFLAGS-wcstol_l.c += $(strtox-CFLAGS)
 CFLAGS-wcstoul_l.c += $(strtox-CFLAGS)
 CFLAGS-wcstoll_l.c += $(strtox-CFLAGS)
 CFLAGS-wcstoull_l.c += $(strtox-CFLAGS)
-CFLAGS-wcstod_l.c += $(strtox-CFLAGS)
-CFLAGS-wcstold_l.c += $(strtox-CFLAGS)
+CFLAGS-wcstod_l.c += $(strtox-CFLAGS) $(config-cflags-wno-ignored-attributes)
+CFLAGS-wcstold_l.c += $(strtox-CFLAGS) $(config-cflags-wno-ignored-attributes)
 CFLAGS-wcstof128_l.c += $(strtox-CFLAGS)
-CFLAGS-wcstof_l.c += $(strtox-CFLAGS)
+CFLAGS-wcstof_l.c += $(strtox-CFLAGS) $(config-cflags-wno-ignored-attributes)
 CPPFLAGS-tst-wchar-h.c += -D_FORTIFY_SOURCE=2
 
+CFLAGS-wcschr.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-wmemchr.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-wmemset.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-mbrtowc.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-wcrtomb.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-wcstoll.c += $(config-cflags-wno-ignored-attributes)
+CFLAGS-wcstoull.c += $(config-cflags-wno-ignored-attributes)
+
 CFLAGS-isoc99_wscanf.c += -fexceptions
 CFLAGS-isoc99_fwscanf.c += -fexceptions
 CFLAGS-isoc99_vwscanf.c += -fexceptions
diff --git a/wctype/Makefile b/wctype/Makefile
index a3540203cc..79d9608cb9 100644
--- a/wctype/Makefile
+++ b/wctype/Makefile
@@ -29,3 +29,5 @@  routines	:= wcfuncs wctype iswctype wctrans towctrans \
 tests	:= test_wctype test_wcfuncs bug-wctypeh
 
 include ../Rules
+
+CFLAGS-wcfuncs.c += $(config-cflags-wno-ignored-attributes)