[Rd] configure failed with curl 7.71.1

[Marco Atzeri]

Hi dev,

can someone confirm if it is a general R 4.0.4 problem
or it is happening only on cygwin ?

checking for curl/curl.h... yes
checking if libcurl is version 7 and >= 7.28.0...
configure: error: libcurl >= 7.28.0 library and headers are required 
with support for https
*** ERROR: configure failed

but https is available on curl:

$ curl --version
curl 7.71.1 (x86_64-pc-cygwin) libcurl/7.71.1 OpenSSL/1.1.1f zlib/1.2.11 
brotli/1.0.7 libidn2/2.2.0 libpsl/0.21.0 (+libidn2/2.0.4) 
libssh/0.8.7/openssl/zlib nghttp2/1.37.0
Release-Date: 2020-07-01
Protocols: dict file ftp ftps gopher http https imap imaps ldap ldaps 
pop3 pop3s rtsp scp sftp smb smbs smtp smtps telnet tftp
Features: AsynchDNS brotli Debug HTTP2 HTTPS-proxy IDN IPv6 Largefile 
libz NTLM NTLM_WB PSL SSL TLS-SRP TrackMemory UnixSockets

$ cygcheck -l libcurl-devel
/usr/bin/curl-config
/usr/include/curl/curl.h
/usr/include/curl/curlver.h
/usr/include/curl/easy.h
/usr/include/curl/mprintf.h
/usr/include/curl/multi.h
/usr/include/curl/stdcheaders.h
/usr/include/curl/system.h
/usr/include/curl/typecheck-gcc.h
/usr/include/curl/urlapi.h
/usr/lib/libcurl.dll.a
/usr/lib/pkgconfig/libcurl.pc
/usr/share/aclocal/libcurl.m4
/usr/share/man/man1/curl-config.1.gz

Regards
Marco