🚀 go-pugleaf

1. Hexadecimal numbers can confuse token parsing.

---- bug1.c
#define A 1

int i = 0x2e+A;
int j = 0x2e+ A;
----

Output of: gcc -E bug1.c
----
# 1 "bug1.c"


int i = 0x2e+A;
int j = 0x2e+ 1 ;
----

2. Macro parameters which are only to be stringified or concatenated, but
not exapanded are nevertheless expanded internally and can lead to
errors and strange effects.

---- bug2.c
#define k(a) #a

char *s = k(k(1,2));
char *t = k(#) k(#undef k) k(x);	/* feature?? */
----

Output of: gcc -E bug2.c
----
bug2.c:3: macro `k' used with too many (2) args
bug2.c:4: invalid preprocessor directive name
# 1 "bug2.c"


char *s = "k(1,2)" ;
char *t = "#"  "#undef k"  k(x);	 
----
--
Andreas Schwab
schwab@ls5.informatik.uni-dortmund.de