[Bug bootstrap/21216] New: Spontaneous cc1 rebuild during parallel make causes build failure.

["green at redhat dot com" <gcc-bugzilla at gcc dot gnu dot org>]

I've built a half-dozen GCC 4.0.0 based compilers in parallel (make -j2) on
Linux without a hitch.  But I received the following error building an sh-elf
toolchain.  make is deciding to rebuild cc1 after cross building much of libgcc
already, and then, when it tries to use this new cc1 (perhaps before it is fully
written?)...

/usr/src/redhat/BUILD/gcc-4.0.0/obj-sh-elf/gcc/xgcc
-B/usr/src/redhat/BUILD/gcc-4.0.0/obj-sh-elf/gcc/ -nostdinc
-B/usr/src/redhat/BUILD/gcc-4.0.0/obj-sh-elf/sh-elf/newlib/ -isystem
/usr/src/redhat/BUILD/gcc-4.0.0/obj-sh-elf/sh-elf/newlib/targ-include -isystem
/usr/src/redhat/BUILD/gcc-4.0.0/newlib/libc/include -B/usr/sh-elf/bin/
-B/usr/sh-elf/lib/ -isystem /usr/sh-elf/include -isystem /usr/sh-elf/sys-include
-O2  -DIN_GCC -DCROSS_COMPILE   -W -Wall -Wwrite-strings -Wstrict-prototypes
-Wmissing-prototypes -Wold-style-definition  -isystem ./include   -g 
-DIN_LIBGCC2 -D__GCC_FLOAT_NOT_NEEDED -Dinhibit_libc -I. -I. -I../../gcc
-I../../gcc/. -I../../gcc/../include -I../../gcc/../libcpp/include  -DL_ashrdi3
-c ../../gcc/libgcc2.c -o libgcc/./_ashrdi3.o
gcc   -g -O2 -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes
-pedantic -Wno-long-long -Wno-variadic-macros -Wold-style-definition   -DIN_GCC
-DCROSS_COMPILE  -W -Wall -Wwrite-strings -Wstrict-prototypes
-Wmissing-prototypes -pedantic -Wno-long-long -Wno-variadic-macros
-Wold-style-definition    -DHAVE_CONFIG_H  -o cc1 \
        c-parse.o c-lang.o stub-objc.o attribs.o c-errors.o c-lex.o c-pragma.o
c-decl.o c-typeck.o c-convert.o c-aux-info.o c-common.o c-opts.o c-format.o
c-semantics.o c-incpath.o cppdefault.o c-ppoutput.o c-cppbuiltin.o prefix.o
c-objc-common.o c-dump.o c-pch.o  c-gimplify.o tree-mudflap.o c-pretty-print.o
main.o  libbackend.a ../libcpp/libcpp.a ../libcpp/libcpp.a  
../libiberty/libiberty.a
/usr/src/redhat/BUILD/gcc-4.0.0/obj-sh-elf/gcc/xgcc
-B/usr/src/redhat/BUILD/gcc-4.0.0/obj-sh-elf/gcc/ -nostdinc
-B/usr/src/redhat/BUILD/gcc-4.0.0/obj-sh-elf/sh-elf/newlib/ -isystem
/usr/src/redhat/BUILD/gcc-4.0.0/obj-sh-elf/sh-elf/newlib/targ-include -isystem
/usr/src/redhat/BUILD/gcc-4.0.0/newlib/libc/include -B/usr/sh-elf/bin/
-B/usr/sh-elf/lib/ -isystem /usr/sh-elf/include -isystem /usr/sh-elf/sys-include
-O2  -DIN_GCC -DCROSS_COMPILE   -W -Wall -Wwrite-strings -Wstrict-prototypes
-Wmissing-prototypes -Wold-style-definition  -isystem ./include   -g 
-DIN_LIBGCC2 -D__GCC_FLOAT_NOT_NEEDED -Dinhibit_libc -I. -I. -I../../gcc
-I../../gcc/. -I../../gcc/../include -I../../gcc/../libcpp/include  -DL_cmpdi2
-c ../../gcc/libgcc2.c -o libgcc/./_cmpdi2.o
xgcc: installation problem, cannot exec 'cc1': No such file or directory
make[2]: *** [libgcc/./_cmpdi2.o] Error 1

Rerunning make gets it going again.

I'll attach more of the relevant log file to this issue.

-- 
           Summary: Spontaneous cc1 rebuild during parallel make causes
                    build failure.
           Product: gcc
           Version: 4.0.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: bootstrap
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: green at redhat dot com
                CC: gcc-bugs at gcc dot gnu dot org
  GCC host triplet: i686-pc-linux-gnu
GCC target triplet: sh-elf


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21216