[Bug preprocessor/24024] New: gcc -E -C processes "\" incorrectly inside C comments

[stefan dot becker at nokia dot com]

Try the following stripped-down example file:

---------------------- dummy.txt -----------------------------
/* Execute example with: gcc -E -P -C -x c dummy.txt
a \
b \
c
*/
---------------------- dummy.txt -----------------------------

i.e. there are continuation lines *inside* C comments.


Result with GCC <= 3.4 (verified with 3.2.3, 3.3.2):

----------------------------------------------------------------
/* Execute example with: gcc -E -P -C -x c dummy.txt
a \
b \
c
*/
----------------------------------------------------------------

i.e. unchanged.


Result with GCC >= 3.4 (verified with 3.4.1, 3.4.3 [RHEL4], 3.4.4, 4.0.0,
4.1-20050625):

----------------------------------------------------------------
/* Execute example with: gcc -E -P -C -x c dummy.txt
a b c
\
c
*/
----------------------------------------------------------------

i.e. the lines were merged but the some of the original contents are still
there! I know this is arcane but I'm using cpp to process #if's and it should
leave the contents of the comments untouched as it is used by another tool down
the line.


I'm not so sure what the standard says about line continuation inside C comments
but if the lines should be merged I would expect the following result:

----------------------------------------------------------------
/* Execute example with: gcc -E -P -C -x c dummy.txt
a b c
*/
----------------------------------------------------------------

which would be OK.

-- 
           Summary: gcc -E -C processes "\" incorrectly inside C comments
           Product: gcc
           Version: 3.4.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: preprocessor
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: stefan dot becker at nokia dot com
                CC: gcc-bugs at gcc dot gnu dot org
  GCC host triplet: i386-redhat-linux
GCC target triplet: i386-redhat-linux


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=24024