How does -U -D and --force work together

[Sonni]

When I have defined both -U, -D and --force arguments it looks like cppcheck still performs some og the combinations of defines that are undefined with the -U argument.

How does these 3 arguments interact ?

[Daniel Marjamäki]

Example code with three bugs (when x,y,z is assigned).

#ifdef A
  x=100/0;
  #ifdef B
    y=100/0;
  #endif
#else
  z=100/0;
#endif

Configurations tested:
cppcheck test.c => "", "A", "A;B" => all bugs are found
cppcheck -DA test.c => "A" => The first bug is found
cppcheck -UA test.c => "" => The last bug is found
cppcheck --force -DA test.c => "A", "A;B" => The two first bugs are found

I guess we should clarify the manual somehow. http://cppcheck.sourceforge.net/manual.html#preprocessor-settings

Do you have some pointer about how we could clarify it.

[Sonni]

It seams to work. I had created the .cppcheck project file by hand and it had an error in the <undefine> tag, which explains why I went through all combinations with the undefined flags.</undefine>

I made a smalle test aswell:

#ifdef A1
int a1=100/0;
#ifdef A2
int a2=100/0;
#endif
#endif

#ifdef B1
int b1=100/0;
#ifdef B2
int b2=100/0;
#endif
#endif

#ifdef C1
int c1=100/0;
#ifdef C2
int c2=100/0;
#endif
#endif

and with different define/undefine's set I get the expected behavior.

For the documentation the key point must be: All flags set with define/-D and undefine/-U will be fixed, all other flags will be tried in combinations when the --force argument is specified.

[Daniel Marjamäki]

For the documentation the key point must be: All flags set with define/-D and undefine/-U will be fixed, all other flags will be tried in combinations when the --force argument is specified.

Yes that is a good point thanks 👍