[Bug lto/44802] New: -flto -fuse-linker-plugin causes undefined references from libc in the link phase

["moonshine at kapsi dot fi" <gcc-bugzilla at gcc dot gnu dot org>]

This works fine without -fuse-linker-plugin (with all object files extracted
from archive). This reduced testcase has some undefined references of its own
but still exposes the bug as shown below. Whole output of linking a complete
program is attached because of its 30 kB size. Also a preprocessed source file
is attached.

gcc -std=gnu99 -fvisibility=hidden -O3 -fomit-frame-pointer -march=pentium4
-flto -fuse-linker-plugin -o xz main.i

--SNAP--
/home/misty/gcc/lib/gcc/i686-pc-linux-gnu/4.5.1/../../../../i686-pc-linux-gnu/bin/ld:
error: hidden symbol 'fgetc' is not defined locally
/home/misty/gcc/lib/gcc/i686-pc-linux-gnu/4.5.1/../../../../i686-pc-linux-gnu/bin/ld:
error: hidden symbol 'ferror' is not defined locally
--SNAP--

main.i was produced with:

gcc -std=gnu99 -DHAVE_CONFIG_H -I. -I../.. 
-DLOCALEDIR=\"/home/misty/gcc/share/locale\" -I../../src/common
-I../../src/liblzma/api -I../../lib -DLZMA_API_STATIC  -pthread
-fvisibility=hidden -Wall -Wextra -Wformat=2 -Winit-self -Wmissing-include-dirs
-Wstrict-aliasing -Wfloat-equal -Wundef -Wshadow -Wpointer-arith
-Wbad-function-cast -Wwrite-strings -Wlogical-op -Waggregate-return
-Wstrict-prototypes -Wold-style-definition -Wmissing-prototypes
-Wmissing-declarations -Wmissing-noreturn -Wredundant-decls -O3
-fomit-frame-pointer -march=pentium4 -flto -fuse-linker-plugin -MT xz-main.o
-MD -MP -MF .deps/xz-main.Tpo -E main.c >main.i


-- 
           Summary: -flto -fuse-linker-plugin causes undefined references
                    from libc in the link phase
           Product: gcc
           Version: 4.5.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: lto
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: moonshine at kapsi dot fi
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: i686-pc-linux-gnu


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44802