"mildsim" <whcui1987@xxxxxxxxx> writes: > /***************************************************************************************************************/ > > Recently, the preprocessor has relaxed its treatment of escaped newlines. Previously, the newline had to immediately follow a backslash. The current implementation allows whitespace in the form of spaces, horizontal and vertical tabs, and form feeds between the backslash and the subsequent newline. The preprocessor issues a warning, but treats it as a valid escaped newline and combines the two lines to form a single logical line. This works within comments and tokens, as well as between tokens. Comments are not treated as whitespace for the purposes of this relaxation, since they have not yet been replaced with spaces. > > /****************************************************************************************************************/ > > > can someone show me an easy example using this feature,such as a hello world example.And why develops this feature? This refers to how the input file is handled by the preprocessor. In the input file, whitespace between a backslash and a newline is ignored. For example, if you run the attached file through gcc -E, it will be turned into "a b". For some background on why this is done, see http://gcc.gnu.org/ml/gcc/2000-05/msg01032.html and http://gcc.gnu.org/PR8270 . Ian
#define A a \ b A
