[petsc-dev] CFLAGS / LDFLAGS and cxx error

[Barry Smith]

On Jul 28, 2010, at 2:00 PM, Wesley Smith wrote:

>>  Nope, they are completely distinct to handle the rare cases where the c++ compiler doesn't like all the valid flags that the C compiler accepts. Is there a way we could have made this fact obvious to users?
> 
> It's a good question.  I found myself completely overwhelmed by the
> ./configure --help output.  I'm wondering if there's a way to
> partition it into smaller subsections similar to how gdb's help has
> different help sections depending on whether you're setting
> breakpoints, examining a backtrace, etc.  petsc is compiling right
> now, so when it's done, I'll have a look at the descriptions for
> CFLAGS and CXXFLAGS.  Posting the reason for the cxx compiler not
> being recognized would definitely help.

    This is really tricky. We would have to parse the output from the compiler/linker and "understand automatically" the problem so we can report it back to the user. In general this is impossible. We could, however, for example handle THIS case by looking for the string:  "file was built for unsupported file format which is not the architecture being linked" and print an error message specific to that string. The problem is if Apple or the compiler writes change one word in their error message our string search no longer works.

   Barry



> 
> wes