Why this multiline macro doesn't work?

Question

Doesn't look like it was parced correctly even. But it looks fine to me.

Maybe it doesn't like newlines? Tried without them.

Maybe it must be in UPPER CASE? I honestly have no idea.

Maybe it doesn't like ////comments?

#define fill(where_l, where_r, where_t, where_b, what_l, what_r, what_t, what_b) \
                                                                    \
    ////lt                                      \
    *p++ = where_l;                   \  
    *p++ = where_t;                   \
    *p++ = 0.5f;                    \
    *p++ = 1.0f;                   \
    *p++ = what_l;                   \
    *p++ = what_t;                   \
                                    \
    ////rt                   \
    *p++ = where_r;                   \
    *p++ = where_t;                   \
    *p++ = 0.5f;                   \
    *p++ = 1.0f;                   \
    *p++ = what_r;                   \
    *p++ = what_t;                   \
                   \
    ////lb                   \
    *p++ = where_l;                   \
    *p++ = where_b;                   \
    *p++ = 0.5f;                   \
    *p++ = 1.0f;                   \
    *p++ = what_l;                   \
    *p++ = what_b;                   \
                   \
    ////rb                   \
    *p++ = where_r;                   \
    *p++ = where_b;                   \
    *p++ = 0.5f;                   \
    *p++ = 1.0f;                   \
    *p++ = what_r;                   \
    *p++ = what_b;                   \

Errors:

1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(569) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(569) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(570) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(570) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(570) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(569) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(571) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(571) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(571) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(569) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(572) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(572) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(572) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(569) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(573) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(573) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(573) : error C2086: 'int *p' : redefinition

Deleted comments completely, now errors are:

1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(569) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(569) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(569) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(570) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(570) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(570) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(571) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(571) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(571) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(572) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(572) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(572) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(574) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(574) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(574) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(575) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(575) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(575) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(576) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(576) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(576) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(577) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(577) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(577) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(578) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(578) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(578) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(579) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(579) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(579) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(581) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(581) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(581) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(582) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(582) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(582) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(583) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(583) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(583) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(584) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(584) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(584) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(585) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(585) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(585) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(586) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(586) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(586) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(588) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(588) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(588) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(589) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(589) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(589) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(590) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(590) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(590) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(591) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(591) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(591) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(592) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(592) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(592) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(593) : error C2143: syntax error : missing ';' before '++'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(593) : error C4430: missing type specifier - int assumed. Note: C++ does not support default-int
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(593) : error C2086: 'int *p' : redefinition
1>        c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(568) : see declaration of 'p'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(641) : error C2297: '*' : illegal, right operand has type 'float *'
1>c:\_src\directxsamples\ex_tut2_showjpg\tut2_vertices.cpp(641) : error C2017: illegal escape sequence

It looks like your post is mostly code, please add some more details.

Here is how I use it:

            float* p = (float*)malloc(999);
            fill(i_im_x, i_im_x + 512.0f,
                i_im_y, i_im_y + 512.0f,
                0.0f, 1.0f,
                0.0f, 1.0f);

Answer 1

You need to do this:

1. Replace all ////xx comments by /* xx */
2. Remove the stray space character after the \\ in following line:

---

*p++ = where_l;                   \ 
                                   ^ stray space here

---

This was not obvious because you cannot see that stray space unless you put the cursor there.

3. Remove the final \\ in the very last line of the macro:

---

 *p++ = what_b;                   \
                                  ^ remove this

---

Working example:

#define fill(where_l, where_r, where_t, where_b, what_l, what_r, what_t, what_b) \
                                                                    \
    /*lt*/                                      \
    *p++ = where_l;                   \
    *p++ = where_t;                   \
    *p++ = 0.5f;                    \
    *p++ = 1.0f;                   \
    *p++ = what_l;                   \
    *p++ = what_t;                   \
    \
    /* rt */                  \
    *p++ = where_r;                   \
    *p++ = where_t;                   \
    *p++ = 0.5f;                   \
    *p++ = 1.0f;                   \
    *p++ = what_r;                   \
    *p++ = what_t;                   \
                   \
    /*lb*/                   \
    *p++ = where_l;                   \
    *p++ = where_b;                   \
    *p++ = 0.5f;                   \
    *p++ = 1.0f;                   \
    *p++ = what_l;                   \
    *p++ = what_b;                   \
                   \
    /*rb*/                   \
    *p++ = where_r;                   \
    *p++ = where_b;                   \
    *p++ = 0.5f;                   \
    *p++ = 1.0f;                   \
    *p++ = what_r;                   \
    *p++ = what_b;

int main(int argc, char **argv) {

  float* p = (float*)malloc(999);
  fill(1, 2, 3, 4, 5, 6, 7, 8)
}