[Bug c++/92670] New: Same error message duplicates for C++20 "deprecated" attribute

[euloanty at live dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92670

            Bug ID: 92670
           Summary: Same error message duplicates for C++20 "deprecated"
                    attribute
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: euloanty at live dot com
  Target Milestone: ---

Here is an example:
[[deprecated("sha1 is no longer a secure algorithm, see wikipedia. The
SHAppening: https://en.wikipedia.org/wiki/SHA-1#The_SHAppening")]] 
inline constexpr void flush(sha1& sh);

Then:

D:\hg\fast_io\examples\0048.hash>g++ -o sha1 sha1.cc -Ofast -std=c++2a
-fconcepts
sha1.cc: In function 'int main(int, char**)':
sha1.cc:16:12: warning: 'constexpr void
fast_io::{anonymous}::flush(fast_io::{anonymous}::sha1&)' is deprecated: sha1
is no longer a secure algorithm, see wikipedia. The SHAppening:
https://en.wikipedia.org/wiki/SHA-1#The_SHAppening
[ttps://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wdeprecated-declarationsdeprecated-declarations]
   16 |  flush(sha1);
      |            ^
In file included from ../../include/fast_io_hash.h:4,
                 from sha1.cc:3:
../../include/fast_io_hash/sha1.h:234:23: note: declared here
  234 | inline constexpr void flush(sha1& sh)
      |                       ^~~~~
sha1.cc:16:12: warning: 'constexpr void
fast_io::{anonymous}::flush(fast_io::{anonymous}::sha1&)' is deprecated: sha1
is no longer a secure algorithm, see wikipedia. The SHAppening:
https://en.wikipedia.org/wiki/SHA-1#The_SHAppening
[ttps://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wdeprecated-declarationsdeprecated-declarations]
   16 |  flush(sha1);
      |            ^
In file included from ../../include/fast_io_hash.h:4,
                 from sha1.cc:3:
../../include/fast_io_hash/sha1.h:234:23: note: declared here
  234 | inline constexpr void flush(sha1& sh)
      |                       ^~~~~


Full source code is here:
https://bitbucket.org/ejsvifq_mabmip/fast_io/src/default/include/fast_io_hash/sha1.h
https://bitbucket.org/ejsvifq_mabmip/fast_io/src/default/examples/0048.hash/sha1.cc