[cfe-dev] svn update then make gives cc1 error: unrecognized command line option '-Wcovered-switch-default'

[Eli Friedman]

On Fri, Oct 5, 2012 at 5:58 PM, Larry Evans <cppljevans at suddenlink.net> wrote:
> On 10/05/12 19:35, Eli Friedman wrote:
>> On Fri, Oct 5, 2012 at 5:25 PM, Larry Evans <cppljevans at suddenlink.net> wrote:
>>> On 10/05/12 13:32, Larry Evans wrote:
>>>   I just ran svn update:
>>>
>>>   ~/download/llvm/svn/llvm $ svn update
>>>   ~/download/llvm/svn/llvm/tools/clang $ svn update
>>>   ~/download/llvm/svn/llvm/tools $ svn co
>>>   http://llvm.org/svn/llvm-project/clang-tools-extra/trunk extra
>>>   ~/download/llvm/svn/llvm/projects/compiler-rt $ svn update
>>>
>>>   However, make resulted in:
>>>
>>>   .
>>>   .
>>>   .
>>>   llvm[1]: Compiling regexec.c for Debug+Asserts build
>>>   cc1: error: unrecognized command line option "-Wcovered-switch-default"
>>>   /bin/rm: cannot remove
>>>
>>> `/home/evansl/download/llvm/svn/build/lib/Support/Debug+Asserts/regexec.d.tmp':
>>>   No such file or directory
>>>   make[1]: ***
>>>   [/home/evansl/download/llvm/svn/build/lib/Support/Debug+Asserts/regexec.o]
>>>   Error 1
>>>   make[1]: Leaving directory
>>>   `/home/evansl/download/llvm/svn/build/lib/Support'
>>>   make: *** [all] Error 1
>>>   ~/download/llvm/svn/build $
>>>
>>>   How can this be corrected?
>>>
>>>   My system is:
>>>
>>>   uname -a
>>>   Linux evansl-desktop 2.6.32-41-generic #90-Ubuntu SMP Tue May 22
>>>   11:29:51 UTC 2012 x86_64 GNU/Linux
>>>
>>>   TIA.
>>>
>>>   -regards,
>>>   Larry
>>> SOLVED:
>>>
>>> Changed Makefile.config to remove the COVERED_SWITCH_DEFAULT macro,
>>> and now it's working:
>>>
>>>   ~/download/llvm/svn/build $ cat Makefile.config|grep switch
>>>   # -Wcovered-switch-default
>>>   #COVERED_SWITCH_DEFAULT = -Wcovered-switch-default
>>>   ~/download/llvm/svn/build $ make
>>>   llvm[0]: Constructing LLVMBuild project information.
>>>   make[1]: Entering directory
>>> `/home/evansl/download/llvm/svn/build/lib/Support'
>>>   llvm[1]: Compiling regexec.c for Debug+Asserts build
>>>   llvm[1]: Compiling system_error.cpp for Debug+Asserts build
>>>   llvm[1]: Building Debug+Asserts Archive Library libLLVMSupport.a
>>
>> Err, this is a guess, but it's possible you're setting the C++
>> compiler to clang++, but not setting the C compiler to clang.
>>
>> -Eli
>
> Thanks Eli.
>
> I've not set anything directly.  I did do the configure step:
>
> ~/download/llvm/svn/llvm $ cd ..
> ~/download/llvm/svn $ cd build
> ~/download/llvm/svn/build $ ls ../llvn/configure
> ../llvn/configure: No such file or directory
> ~/download/llvm/svn/build $ ls ../llvm/configure
> ../llvm/configure
> ~/download/llvm/svn/build $ ../llvm/configure
> checking for clang... no
> checking for llvm-gcc... no
> checking for gcc... gcc
> .
> .
> .
>
> and maybe that did what you say.  Hmmm.  This is not the
> 1st time I've built clang; so, maybe something's left over
> from the last build.
>
> Where would I check to see which compiler is being used?

You can look in config.log for lines starting with CC= and CXX= .

-Eli