diff options
Diffstat (limited to 'gcc/cppmacro.c')
| -rw-r--r-- | gcc/cppmacro.c | 22 |
1 files changed, 17 insertions, 5 deletions
diff --git a/gcc/cppmacro.c b/gcc/cppmacro.c index 3dc973f3b83..03a9a99659d 100644 --- a/gcc/cppmacro.c +++ b/gcc/cppmacro.c @@ -53,6 +53,14 @@ static unsigned int find_param PARAMS ((const cpp_token *, const cpp_token *)); static cpp_toklist * alloc_macro PARAMS ((cpp_reader *, struct macro_info *)); +/* These are all the tokens that can have something pasted after them. + Comma is included in the list only to support the GNU varargs extension + (where you write a ## b and a disappears if b is an empty rest argument). */ +#define CAN_PASTE_AFTER(type) \ +((type) <= CPP_LAST_EQ || (type) == CPP_COLON || (type) == CPP_HASH \ + || (type) == CPP_DEREF || (type) == CPP_DOT || (type) == CPP_NAME \ + || (type) == CPP_INT || (type) == CPP_FLOAT || (type) == CPP_NUMBER \ + || (type) == CPP_MACRO_ARG || (type) == CPP_PLACEMARKER || (type) == CPP_COMMA) /* Scans for a given token, returning the parameter number if found, or 0 if not found. Scans from FIRST to TOKEN - 1 or the first @@ -192,7 +200,6 @@ count_params (pfile, info) } else { - info->flags |= GNU_REST_ARGS; if (CPP_PEDANTIC (pfile)) cpp_pedwarn (pfile, "ISO C does not permit named varargs parameters"); @@ -294,9 +301,6 @@ parse_define (pfile, info) /* Constraint 6.10.3.5 */ if (!(info->flags & VAR_ARGS) && is__va_args__ (pfile, token)) return 1; - /* It might be worth doing a check here that we aren't a - macro argument, since we don't store the text of macro - arguments. This would reduce "len" and save space. */ } info->ntokens++; if (TOKEN_SPELL (token) == SPELL_STRING) @@ -463,7 +467,15 @@ save_expansion (pfile, info) continue; case CPP_PASTE: - dest[-1].flags |= PASTE_LEFT; + /* Set the paste flag on the token to our left, unless there + is no possible token to which it might be pasted. That + is critical for correct operation under some circumstances; + see gcc.dg/cpp/paste6.c. */ + if (CAN_PASTE_AFTER (dest[-1].type) || (dest[-1].flags & NAMED_OP)) + dest[-1].flags |= PASTE_LEFT; + else if (CPP_OPTION (pfile, warn_paste)) + cpp_warning_with_line (pfile, dest[-1].line, dest[-1].col, + "nothing can be pasted after this token"); continue; case CPP_HASH: |