It seems to be libtool that's dropping the -specs option:

/usr/bin/libtool --mode=link gcc  -O2 -g -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fexceptions -fstack-protector-strong -grecord-gcc-switches -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -mcet -fcf-protection  -D_REENTRANT -Wl,-z,relro  -specs=/usr/lib/rpm/redhat/redhat-hardened-ld -o libglib.la -rpath /usr/lib64 -version-info 0:10:0 -release 1.2 -export-dynamic garray.lo gcache.lo gcompletion.lo gdataset.lo gdate.lo gerror.lo ghash.lo ghook.lo giochannel.lo giounix.lo glist.lo gmain.lo gmem.lo gmessages.lo gmutex.lo gnode.lo gprimes.lo grel.lo gscanner.lo gslist.lo gstrfuncs.lo gstring.lo gtimer.lo gtree.lo gutils.lo
libtool: link: gcc -shared  -fPIC -DPIC  .libs/garray.o .libs/gcache.o .libs/gcompletion.o .libs/gdataset.o .libs/gdate.o .libs/gerror.o .libs/ghash.o .libs/ghook.o .libs/giochannel.o .libs/giounix.o .libs/glist.o .libs/gmain.o .libs/gmem.o .libs/gmessages.o .libs/gmutex.o .libs/gnode.o .libs/gprimes.o .libs/grel.o .libs/gscanner.o .libs/gslist.o .libs/gstrfuncs.o .libs/gstring.o .libs/gtimer.o .libs/gtree.o .libs/gutils.o    -O2 -g -fstack-protector-strong -grecord-gcc-switches -m64 -mtune=generic -mcet -Wl,-z -Wl,relro   -Wl,-soname -Wl,libglib-1.2.so.0 -o .libs/libglib-1.2.so.0.0.10

Any idea how to get libtool to pass -specs to gcc?

I should mention that this is an ancient package so I use the system libtool rather than the one shipped with the original source, which may be a related thing.

(In reply to Paul Howarth from comment #1)
> Any idea how to get libtool to pass -specs to gcc?

I asked about this recently here:

https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/thread/FILPDYHXHOUOYFP65PS7SJNH5OD4RBUS/

I do not know yet how this is supposed to work.

This bug appears to have been reported against 'rawhide' during the Fedora 29 development cycle.
Changing version to '29'.

This bug appears to have been reported against 'rawhide' during the Fedora 32 development cycle.
Changing version to 32.

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