[Bug bootstrap/18288] New: remaking existing build after cvs update gives configure recheck problems

["mark at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

When updating a source try (through contrib/gcc_update) and typing make in the
build directory configure recheck fails often for the runtime libraries
(libc++-v3, libjava, boehmgc, libffi, etc.) Here is an example for libmudflap:

make[1]: Entering directory `/home/mark/src/gcc-obj/i686-pc-linux-gnu/libmudflap'
/bin/sh ./config.status --recheck
running /bin/sh /home/mark/src/gcc/libmudflap/configure 
--cache-file=./config.cache --host=i686-pc-linux-gnu --build=i686-pc-linux-gnu
--enable-multilib --enable-java-awt=gtk --prefix=/usr/local/gcc35
--with-gcc-version-trigger=/home/mark/src/gcc/gcc/version.c
--enable-languages=c,c++,java --program-transform-name=s,y,y,
--srcdir=../../../gcc/libmudflap --with-target-subdir=i686-pc-linux-gnu
CPPFLAGS=-O2 -g -O2 build_alias=i686-pc-linux-gnu host_alias=i686-pc-linux-gnu 
--no-create --no-recursion
configure: loading cache ./config.cache
configure: error: `target_alias' was not set in the previous run
configure: error: changes in the environment can compromise the build
configure: error: run `make distclean' and/or `rm ./config.cache' and start
overmake[1]: *** [config.status] Error 1
make[1]: Leaving directory
`/home/mark/src/gcc-obj/i686-pc-linux-gnu/libmudflap'make: ***
[all-target-libmudflap] Error 2

A workaround is deleting that whole subdirectory and trying make from the
toplevel build directory again.

-- 
           Summary: remaking existing build after cvs update gives configure
                    recheck problems
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: bootstrap
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: mark at gcc dot gnu dot org
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18288