[Cocci] Strange behavior with replacing multiple typedefs

[Moustafa Mahmoud]

Hello all,
I am facing this problem with typedefs, what I am trying to achieve is
convering multiple typedefs into single ones.


typedef int x,y;

into :

typedef int x;
typedef int y;


when I try to replace them inside functions, everything works as expected\

My Rule :
@rule1@
identifier fn;
type t;
metavariable mm;
@@

++ typedef t mm;
fn(...){
<+...
- typedef t mm;
...+>
}

The C Code

typedef int;
typedef int mr,e4;

int main()
{
typedef int sss, ssd;
}

The Diff :
diff =
--- typedef.c
+++ /tmp/cocci-output-91048-e42770-typedef.c
@@ -3,7 +3,8 @@
typedef int;
typedef int mr,e4;

+typedef int ssd;
+typedef int sss;
int main()
{
- typedef int sss, ssd;
}
\ No newline at end of file


However if I try to generalize it

@rule1@
type t;
metavariable mm;
@@

++ typedef t mm;
- typedef t mm;



The C Code:

typedef int;
typedef int mr,e4;

int main()
{
typedef int sss, ssd;
}

What I get is this :

typedef int;
-typedef int mr,e4;
+typedef int e4;
+typedef int mr;
+typedef int;

int main()
{
- typedef int sss, ssd;
+ typedef int ssd;
+ typedef int sss;
+ typedef int;
}
\ No newline at end of file


You can notice the extra "+ typedef int;" , why are those produced ? is
there a way to achieve what want without them ?

Thank you very much.

[Julia Lawall]

Post by Moustafa Mahmoud
Hello all,
I am facing this problem with typedefs, what I am trying to achieve is convering multiple typedefs into single ones. 
typedef int x,y;
typedef  int x;
typedef int y;
when I try to replace them inside functions, everything works as expected\
@rule1@
identifier fn;
type t;
metavariable mm;
@@
++ typedef t mm;
fn(...){
<+...
- typedef t mm;
...+>
}
The C Code 
typedef int;
typedef int mr,e4;
int main()
{
    typedef int sss, ssd;
}
diff =
--- typedef.c
+++ /tmp/cocci-output-91048-e42770-typedef.c
@@ -3,7 +3,8 @@
 typedef int;
 typedef int mr,e4;
+typedef int ssd;
+typedef int sss;
 int main()
 {
-    typedef int sss, ssd;
 }
\ No newline at end of file
However if I try to generalize it 
@rule1@
type t;
metavariable mm;
@@
++ typedef t mm;
- typedef t mm;
typedef int;
typedef int mr,e4;
int main()
{
    typedef int sss, ssd;
}
 typedef int;
-typedef int mr,e4;
+typedef int e4;
+typedef int mr;
+typedef int;
 int main()
 {
-    typedef int sss, ssd;
+    typedef int ssd;
+    typedef int sss;
+    typedef int;
 }
\ No newline at end of file
You can notice the extra  "+  typedef int;" , why are those produced ? is there a way to achieve what  want without them ?

Wow, I'm thrilled that it worked at all :) I knew that that would work
for eg int x,y,z;, but I didn't realize that it would work for typedefs
too.

I have the impression that it is pulling out the individual typedefs like
you asked, but then it is not actually deleting the typedef t ; part.
That is, it is not adding typedef int; it is just not removing the
original typedef after pulling out eg mr and e4. I will see if I can fix
it. In the short term , I don't see any workaround, unfortunately.

julia