After a lot of investigating I noticed that I was indeed using the 32 bit env vars instead of the 64 bit env vars. So I now used the 64 bit vars and reran cpan to upgrade the DBI module. Now it fails with the following messages.
C:\Perl64\bin\perl.exe -p -e "s/~DRIVER~/Perl/g" Driver.xst >
+Perl.xsi
C:\Perl64\bin\perl.exe C:\Perl64\lib\ExtUtils\xsubpp -typemap
+ C:\Perl64\lib\ExtUtils\typemap -typemap typemap Perl.xs > Perl.xsc
+&& C:\Perl64\bin\perl.exe -MExtUtils::Command -e mv -- Perl.xsc Perl.
+c
cl -c -nologo -GF -W3 -MD -Zi -DNDEBUG -Ox -GL -fp:precise
+-DWIN32 -D_CONSOLE -DNO_STRICT -DWIN64 -DCONSERVATIVE -DPERL_TEXTMODE
+_SCRIPTS -DUSE_SITECUSTOMIZE -DPERL_IMPLICIT_CONTEXT -DPERL_IMPLICIT_
+SYS -DUSE_PERLIO -MD -Zi -DNDEBUG -Ox -GL -fp:precise -DVERSION=\"
+1.642\" -DXS_VERSION=\"1.642\" "-IC:\Perl64\lib\CORE" Perl.c
Perl.c
C:\Perl64\lib\CORE\perl.h(621): fatal error C1083: Cannot open include
+ file: 'stdarg.h': No such file or directory
NMAKE : U1077:
Stop.
TIMB/DBI-1.642.tar.gz
C:\bin\nmake.exe -- NOT OK
Failed during this command:
TIMB/DBI-1.642.tar.gz : make NO
cpan>
I shall keep investigating on this issuer.