Configuration Information [Automatically generated, do not change]: Machine: i386 OS: linux-gnu Compiler: gcc Compilation CFLAGS: -DPROGRAM='bash' -DCONF_HOSTTYPE='i386' -DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='i386-redhat-linux-gnu' -DCONF_VENDOR='redhat' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash' -DSHELL -DHAVE_CONFIG_H -I. -I. -I./include -I./lib -D_GNU_SOURCE -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m32 -march=i586 -mtune=generic -fasynchronous-unwind-tables uname output: Linux noname 2.6.29.4-167.fc11.i686.PAE #1 SMP Wed May 27 17:28:22 EDT 2009 i686 i686 i386 GNU/Linux Machine Type: i386-redhat-linux-gnu
Bash Version: 4.0 Patch Level: 16 Release Status: release Description: During the compilation of the linux kernel (configured to user mode linux) I've discovered the following problem of bash 4.0 (which is now delivered by Fedora 11): If an environmental variable contains a "." in its name, the new bash 4.0 filters out these variables. They will not be visible via "set" nor will they be inherited to executed sub-shells or processes. This behavior explains the compile problem: - the kernel's make system uses make variables like "CPPFLAGS_vmlinux.lds" - they are exported via "export" in the Makefile - subsequent make processes are started (via bash, since SHELL=/bin/bash is set in the Makefile) - they don't get the variable inherited, because the bash filters it out - the build will fail since the called Makefile expects this variable I've installed for testing purposes bash 3.2 on this system and the problems were gone. Repeat-By: Fedora 10 (GNU bash, version 3.2.39(1)-release (i386-redhat-linux-gnu)) $ env foo.foo=bar bash $ set |grep foo foo.foo=bar $ cat /proc/$$/environ |grep foo\.foo Binary file (standard input) matches $ bash $ set |grep foo foo.foo=bar Fedora 11 (GNU bash, version 4.0.16(1)-release (i386-redhat-linux-gnu)) $ env foo.foo=bar bash $ set |grep foo $ cat /proc/$$/environ |grep foo\.foo Binary file (standard input) matches $ bash $ set |grep foo $ cat /proc/$$/environ |grep foo\.foo $ This shows, that in F11: * the environment variable foo.foo is not added to the bash's list of environment variables accessible via "set" * the variable is still in the process's environment * the variable will be filtered out when the bash executes a subsequent process This change may also affect other make-based build systems which rely on the fact that a make variable which is exported via the keyword "export" in the Makefile is accessible in nested calls of make. Best regards, Christian
