With latest GPGME 1.17.0 the new Qt util.cpp FTBFS on i386 only due a missing _FILE_OFFSET_BITS define as required by included src/gpgme.h with the following being the relevant part of the build log:
/bin/bash ../../../libtool --tag=CXX --mode=compile g++ -DHAVE_CONFIG_H -I. -I../../../../lang/qt/src -I../../../conf -I../../../../lang/cpp/src -I../../../src -I/usr/include/i386-linux-gnu/qt5/QtCore -I/usr/include/i386-linux-gnu/qt5 -fpic -I/usr/include -DBUILDING_QGPGME -Wsuggest-override -Wzero-as-null-pointer-constant -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -fdebug-prefix-map=/<<PKGBUILDDIR>>=. -fstack-protector-strong -Wformat -Werror=format-security -c -o util.lo ../../../../lang/qt/src/util.cpp
libtool: compile: g++ -DHAVE_CONFIG_H -I. -I../../../../lang/qt/src -I../../../conf -I../../../../lang/cpp/src -I../../../src -I/usr/include/i386-linux-gnu/qt5/QtCore -I/usr/include/i386-linux-gnu/qt5 -fpic -I/usr/include -DBUILDING_QGPGME -Wsuggest-override -Wzero-as-null-pointer-constant -Wdate-time -D_FORTIFY_SOURCE=2 -g -O2 -fdebug-prefix-map=/<<PKGBUILDDIR>>=. -fstack-protector-strong -Wformat -Werror=format-security -c ../../../../lang/qt/src/util.cpp -fPIC -DPIC -o .libs/util.o
...
In file included from ../../../../lang/qt/src/util.h:37:0,
from ../../../../lang/qt/src/util.cpp:34:
../../../src/gpgme.h:111:2: error: #error GPGME was compiled with _FILE_OFFSET_BITS = 64, please see the section "Largefile support (LFS)" in the GPGME manual.
#error GPGME was compiled with _FILE_OFFSET_BITS = 64, please see the section "Largefile support (LFS)" in the GPGME manual.
^~~~~Please see the included external link for a build log (Ubuntu Focal 20.04 i386) which demonstrates the above failure. Due not being a Qt programmer I am not sure what is causing the above issue for i386 only, but adding the following hack in lang/qt/src/util.h just prior to #include <gpgme.h> does fix the i386 build:
#ifndef _FILE_OFFSET_BITS # define _FILE_OFFSET_BITS 64 #endif
No doubt there is a proper way to resolve this FTBFS for i386 builds other than this hack, but it works for now!