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Yes, I'm looking into that.
Thanks.
I'd rather be phishing!
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Fighting to solve old plan C errors, I met another issue: error C2143: syntax error
I have the following code:
typedef struct test test_t;
struct test
{
const char* name;
const char* name_option;
...
...
};
and
test_t test_123 = {
.name = "Bibi", .name_option = "Bibi_One",
};
How can I get rig of this error ?
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This form of initialization is valid in GNU C, and is valid in other compilers only if they support C99 or later. I don't remember off-hand whether this is supported in C++.
You can make this compatible with C89 by adding the missing initializers, e.g.:
test_t test123 = { "Bibi", "Bibi_one", foo, bar };
Where foo and bar are the values for missing members in the struct.
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.
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Get rid of the member names in the initalization, it's not valid in C++. You can only pass values, and these will be used to initialize the members of the struct in the order of their definition. You don't need to provide values for all members - if you don't, the rest will use default values:
test_t test_123 = { "Bibi", "Bibi_One" };Special case: if you try to initialize a C array in this manner with less values than it's size, the remainder of the array will be initialized with the last value of your initializer list. This code will initialize your entire array with 1s:
int my_array[9] = {1};You can read up on this topic in many articles on the web, just use the correct search term: initializer list.
GOTOs are a bit like wire coat hangers: they tend to breed in the darkness, such that where there once were few, eventually there are many, and the program's architecture collapses beneath them. (Fran Poretto)
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Thank you all of you, it works.
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I have a legacy C code:
char* file_name[0];
which generate a warning: warning C4200: nonstandard extension used : zero-sized array in struct/union
it is correct to write:
char* file_name[_MAX_PATH];
? I don't know the impact of this modify...
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_Flaviu wrote: it is correct to write:
char* file_name[_MAX_PATH];
Yes, it is correct presuming you are going to define the array of pointers
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Or
char* file_name[1];
? anyway, is more than 0 
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Well, it all depends upon what you are going to achieve... 
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_Flaviu wrote: Or
char* file_name[1];
Yes.
The only reason someone would declare zero-length is to dynamic allocate the array. You should change the array length to [1]. If you change it to _MAX_PATH (260) then you will be wasting 1036 bytes on a 32 bit machine and wasting 2072 bytes on a 64 bit machine.
Wasting bytes is punishable by death.
Best Wishes,
-David Delaune
modified 6-Aug-19 5:37am.
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Quote: You should change the array length to [1]
Quote: Wasting bytes is punishable by death
Take your own conclusions. 
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Hmmm,
The law states that wasting bytes less or equal to 1 * sizeof(pointer) is allowed but only in the month of August.
I guess he could remove the array qualifier but then that would probably break his compile.
Best Wishes,
-David Delaune
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Disabling the warning is an option.
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Thank you !
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Quote: _MAX_PATH (260) then you will be wasting 236 bytes on a 32 bit machine and wasting 472 bytes on a 64 bit machine
Hey David, the math there is not clear to me. Do I need more caffeine this morning?
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CPallini wrote: Do I need more caffeine this morning?
No, but I do...
Best Wishes,
-David Delaune
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If you are on C11 ... C11 6.7.9/14 allows the option
char file_name[];
It was addedd for exactly that reason
In vino veritas
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That is not a struct or a union. Is there some other code that you need to show us?
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The original code is:
typedef struct {
....
....
char* file_name[0];
};
also, I get another warning here:
warning C4094: untagged 'struct' declared no symbols
I don't know how to get rid of this warnings ...
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You are using a typedef but have not given it the name that you wish to use. It should be something like:
typedef struct {
....
....
char* file_name[0];
} myStruct;
Also the comment on the last line makes no sense; firstly it is declaring an aray of pointers rather than characters. And secondly, you should not store Unicode characters in a char type array. It will most likely cause problems at run time.
The zero length array is possibly valid, but it depends on how the code uses the struct. It can be used as a placeholder name for space that will be allocated for a dynamic structure at run time. Something like:
struct foo
{
int i;
char text[0];
};
struct foo* myFoo = (struct foo*)malloc(sizeof(struct foo) + 20);
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I was about to write an answer when i saw this. Yes, zero length char arrays at the end of a struct appeared to be quite common in C programming some years (or decades, rather) ago. I haven't seen it in any C++ code ever, although it probably works the same. Whatever you wish to achieve, there's probably a better solution available in C++ syntax. Usually, std::string is the go to solution here.
That said, yes, it must be char [], not char* [], otherwise it doesn't make any sense at all.
GOTOs are a bit like wire coat hangers: they tend to breed in the darkness, such that where there once were few, eventually there are many, and the program's architecture collapses beneath them. (Fran Poretto)
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Stefan_Lang wrote: it doesn't make any sense at all.
Sadly true of so much that we see here.
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pretty sure you could just use char* name;
since the array size is 0.
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