[Bug preprocessor/32271] New: Incorrect warnings in disabled code.

[Bug preprocessor/32271] New: Incorrect warnings in disabled code.

[pcmoen at gmail dot com]

The preprocessor will report warnings when there is an unterminated ' or " in a
disabled section.

Example code that triggers two warnings:
**** Code begin ****
#if 0
This shouln"t cause a problem.
This shouln't cause a problem.
#endif

int
main()
{
        return 0;
}
**** Code end ****

Output from the preprocessor:
$ cpp-4.2 -v -save-temps bug.cpp 
Using built-in specs.
Target: i486-linux-gnu
Configured with: ../src/configure -v
--enable-languages=c,c++,fortran,objc,obj-c++,treelang --prefix=/usr
--enable-shared --with-system-zlib --libexecdir=/usr/lib
--without-included-gettext --enable-threads=posix --enable-nls
--with-gxx-include-dir=/usr/include/c++/4.2 --program-suffix=-4.2
--enable-clocale=gnu --enable-libstdcxx-debug --enable-mpfr
--enable-targets=all --disable-werror --enable-checking=release
--build=i486-linux-gnu --host=i486-linux-gnu --target=i486-linux-gnu
Thread model: posix
gcc version 4.2.1 20070528 (prerelease) (Ubuntu 4.2-20070528-0ubuntu2)
 /usr/lib/gcc/i486-linux-gnu/4.2.1/cc1plus -E -quiet -v -D_GNU_SOURCE bug.cpp
-mtune=generic -fpch-preprocess
ignoring nonexistent directory "/usr/local/include/i486-linux-gnu"
ignoring nonexistent directory
"/usr/lib/gcc/i486-linux-gnu/4.2.1/../../../../i486-linux-gnu/include"
ignoring nonexistent directory "/usr/include/i486-linux-gnu"
#include "..." search starts here:
#include <...> search starts here:
 /usr/include/c++/4.2
 /usr/include/c++/4.2/i486-linux-gnu
 /usr/include/c++/4.2/backward
 /usr/local/include
 /usr/lib/gcc/i486-linux-gnu/4.2.1/include
 /usr/include
End of search list.
# 1 "bug.cpp"
# 1 "<built-in>"
# 1 "<command-line>"
# 1 "bug.cpp"
bug.cpp:2:12: warning: missing terminating " character
bug.cpp:3:12: warning: missing terminating ' character





int
main()
{
 return 0;
}


-- 
           Summary: Incorrect warnings in disabled code.
           Product: gcc
           Version: 4.2.1
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: preprocessor
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: pcmoen at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32271

[Bug preprocessor/32271] Incorrect warnings in disabled code.

[pcmoen at gmail dot com]

------- Comment #1 from pcmoen at gmail dot com  2007-06-10 09:25 -------
Created an attachment (id=13672)
 --> (http://gcc.gnu.org/bugzilla/attachment.cgi?id=13672&action=view)
Test case that shows the error.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32271

[Bug preprocessor/32271] Incorrect warnings in disabled code.

[pinskia at gcc dot gnu dot org]

------- Comment #2 from pinskia at gcc dot gnu dot org  2007-06-10 09:34 -------
Actually the warning is correct as the code is undefined at compile time and
this is documented:

# Do not use @code{#if 0} for comments which are not C code.  Use a real
# comment, instead.  The interior of @code{#if 0} must consist of complete
# tokens; in particular, single-quote characters must balance.



*** This bug has been marked as a duplicate of 14634 ***


-- 

pinskia at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|                            |DUPLICATE


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32271