http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51020
Bug #: 51020
Summary: %{...; :default} spec lines cause all switches to be
validated
Classification: Unclassified
Product: gcc
Version: 4.6.2
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: driver
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: cjwat...@ubuntu.com
This is a reduced test case from a cmake test failure manifesting on Ubuntu ARM
(https://bugs.launchpad.net/bugs/887377):
$ gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/usr/lib/gcc/i686-linux-gnu/4.6/lto-wrapper
Target: i686-linux-gnu
Configured with: ../src/configure -v --with-pkgversion='Ubuntu/Linaro
4.6.2-2ubuntu1' --with-bugurl=file:///usr/share/doc/gcc-4.6/README.Bugs
--enable-languages=c,c++,fortran,objc,obj-c++,go --prefix=/usr
--program-suffix=-4.6 --enable-shared --enable-linker-build-id
--with-system-zlib --libexecdir=/usr/lib --without-included-gettext
--enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.6
--libdir=/usr/lib --enable-nls --with-sysroot=/ --enable-clocale=gnu
--enable-libstdcxx-debug --enable-libstdcxx-time=yes --enable-plugin
--enable-objc-gc --enable-targets=all --disable-werror --with-arch-32=i686
--with-tune=generic --enable-checking=release --build=i686-linux-gnu
--host=i686-linux-gnu --target=i686-linux-gnu
Thread model: posix
gcc version 4.6.2 (Ubuntu/Linaro 4.6.2-2ubuntu1)
$ cat specs
*asm_cpu_spec:
%{mcpu=generic-*:-march=%*; :%{mcpu=*:-mcpu=%*} %{march=*:-march=%*}}
$ gcc -specs=specs ---
gcc: fatal error: no input files
compilation terminated.
$ gcc ---
gcc: error: unrecognized option ‘---’
gcc: fatal error: no input files
compilation terminated.
cmake (which I'm not responsible for; I'm just trying to build it) has a
facility to try to work out whether compiler options are valid, and apparently
looks for "unrecognized option" on stderr. I'm not exactly a fan of matching
human-readable error output like this, but this spec line currently has the
side-effect of validating all switches, and I don't think that can possibly be
its intent.
This spec line was added in this commit:
http://gcc.gnu.org/viewcvs?view=revision&revision=178731
I think the `validate_switches' function should only mark matching switches as
valid if `len' is non-zero.
