When compiling gcc, I've sometimes seen errors arise from commands where the compiler is xgcc, even when not bootstrapping. Presumably this is the newly generated compiler being used as a second stage to build essential run-time libraries, and not (as I used to think) the --disable-bootstrap configure option being ignored. So far so good ... but my question is, where does the configuration (specifically Makefile) for that second stage build come from? To be more specific : using the Debian Stretch gcc-6 source package (gcc-6.3.0-18), I'm seeing problems with the second stage build of libiberty which manifest later as the appended error; xgcc: error: ../libiberty/pic/concat.o: No such file or directory Indeed there is no such file in gcc-objs/x86_64-pc-linux-gnu/libiberty/pic/ (in fact there isn't a pic/ folder either) though it's present in the first stage build, in gcc-objs/libiberty/pic/ Why is the second stage build of libiberty so different? Well, let's look at the Makefiles in each folder. ----------------------------------------------------------------------- diff '/home/brian/Projects/ghdl/2017/gcc-objs/libiberty/Makefile' '/home/brian/Projects/ghdl/2017/gcc-objs/x86_64-pc-linux- gnu/libiberty/Makefile' 57c57 < CC = gcc --- > CC = /home/brian/Projects/ghdl/2017/gcc-objs/./gcc/xgcc -B/home/brian/Projects/ghdl/2017/gcc-objs/./gcc/ -B/opt/ghdl/gcc/x86_64-pc-linux-gnu/bin/ -B/opt/ghdl/gcc/x86_64-pc- linux-gnu/lib/ -isystem /opt/ghdl/gcc/x86_64-pc-linux-gnu/include -isystem /opt/ghdl/gcc/x86_64-pc-linux-gnu/sys-include -isystem /home/brian/Projects/ghdl/2017/gcc-objs/sys-include 64c64 < PICFLAG = -fpic --- > PICFLAG = 113c113 < enable_shared = yes --- > enable_shared = no ----------------------------------------------------------------------- ... well the -fpic flag went missing somehow. I'm not actually clear if this is intended behaviour but it seems odd. At this point I'm stuck, having no clear idea what derives the latter Makefile, or why it drops -fpic, or how to control the behaviour (other than modifying the Makefile by hand each time I run Configure. There HAS to be a better way!). Or why it used to work with gcc-4.9 but not gcc-6.3. But I'd like to know how these options get passed around and the intended way to change them. -- Brian point of failure below... ---------------------------------------------------------------------- : # Make libgnatprj.so /home/brian/Projects/ghdl/2017/gcc-objs/./gcc/xgcc -B/home/brian/Projects/ghdl/2017/gcc-objs/./gcc/ -B/opt/ghdl/gcc/x86_64-pc-linux-gnu/bin/ -B/opt/ghdl/gcc/x86_64-pc- linux-gnu/lib/ -isystem /opt/ghdl/gcc/x86_64-pc-linux-gnu/include -isystem /opt/ghdl/gcc/x86_64-pc-linux-gnu/sys-include -isystem /home/brian/Projects/ghdl/2017/gcc-objs/sys-include -o libgnatprj.so.6 -shared -fPIC -Wl,--soname,libgnatprj.so.6 -Wl,--no- allow-shlib-undefined \ obj-shared/ali.o obj-shared/ali-util.o obj-shared/butil.o obj- shared/binderr.o obj-shared/errout.o obj-shared/erroutc.o obj- shared/errutil.o obj-shared/err_vars.o obj-shared/fname-uf.o obj- shared/fmap.o obj-shared/impunit.o obj-shared/lib-util.o obj- shared/makeutl.o obj-shared/mlib.o obj-shared/mlib-fil.o obj- shared/mlib-tgt.o obj-shared/mlib-tgt-specific.o obj-shared/mlib-utl.o obj-shared/osint.o obj-shared/osint-c.o obj-shared/prj.o obj- shared/prj-attr.o obj-shared/prj-attr-pm.o obj-shared/prj-com.o obj- shared/prj-conf.o obj-shared/prj-dect.o obj-shared/prj-env.o obj- shared/prj-err.o obj-shared/prj-ext.o obj-shared/prj-makr.o obj- shared/prj-nmsc.o obj-shared/prj-pars.o obj-shared/prj-part.o obj- shared/prj-pp.o obj-shared/prj-proc.o obj-shared/prj-strt.o obj- shared/prj-tree.o obj-shared/prj-util.o obj-shared/restrict.o obj- shared/rident.o obj-shared/scng.o obj-shared/sfn_scan.o obj- shared/sinfo-cn.o obj-shared/sinput-c.o obj-shared/sinput-p.o obj- shared/style.o obj-shared/styleg.o obj-shared/stylesw.o obj- shared/switch.o obj-shared/switch-m.o obj-shared/targparm.o obj- shared/tempdir.o obj-shared/sdefault.o obj-shared/link.o obj- shared/prefix.o ../libiberty/pic/concat.o ../libiberty/pic/filename_cmp.o ../libiberty/pic/lrealpath.o ../libiberty/pic/safe-ctype.o ../libiberty/pic/xexit.o ../libiberty/pic/xmalloc.o ../libiberty/pic/xstrdup.o \ -L../../gcc/ada/rts -lgnat-6 \ -L../libgnatvsn -lgnatvsn xgcc: error: ../libiberty/pic/concat.o: No such file or directory xgcc: error: ../libiberty/pic/filename_cmp.o: No such file or directory xgcc: error: ../libiberty/pic/lrealpath.o: No such file or directory xgcc: error: ../libiberty/pic/safe-ctype.o: No such file or directory xgcc: error: ../libiberty/pic/xexit.o: No such file or directory xgcc: error: ../libiberty/pic/xmalloc.o: No such file or directory xgcc: error: ../libiberty/pic/xstrdup.o: No such file or directory Makefile:76: recipe for target 'libgnatprj.so.6' failed make[2]: *** [libgnatprj.so.6] Error 1 make[2]: Leaving directory '/home/brian/Projects/ghdl/2017/gcc- objs/x86_64-pc-linux-gnu/libgnatprj' Makefile:16418: recipe for target 'all-target-libgnatprj' failed
