Increase string literal length limit

Question

I have a lot of string literals that are bigger than 65535 bytes. I'm not allowed to save these strings to seperate files, how can I workaround with the string limit?

https://stackoverflow.com/a/11488682/7821462
MSVC: 2048
GCC: No Limit (up to 100,000 characters), but gives warning after 510 characters:
String literal of length 100000 exceeds maximum length 509 that
C90 compilers are required to support

One option is to split strings to different variables inside single file and then use array of pointers to these variables. It makes your life harder but that's the nature — unalignedmemoryaccess, Jul 24 '17 at 08:33
*Why* can't you use files (or some other database) to store the texts? What requirement do you have that doesn't allow that? — Some programmer dude, Jul 24 '17 at 08:34
@Rakete1111 I need to make strings work with MSVC first, then gcc later. — MiP, Jul 24 '17 at 08:36
@Someprogrammerdude The requirement is I need to ship everything in one single executable file. — MiP, Jul 24 '17 at 08:37
Answer for MSVC: https://stackoverflow.com/questions/31460913/string-length-limit-in-msvc-during-compile — Rakete1111, Jul 24 '17 at 08:38
@Rakete1111 Concatenating strings only works when it's smaller than 65535 bytes https://msdn.microsoft.com/en-us/library/sx08afx2.aspx — MiP, Jul 24 '17 at 08:40
Write some custom class using a `std::vector` that allows concatenating string literals beyond the limit? — MadScientist, Jul 24 '17 at 08:45
Write some code to auto-gen a header of string fragments and some code to join it back together. Grind your input through your tool and then use your auto-gen'ed code at run time. — Joe, Jul 24 '17 at 08:56
If this isn't overkill, compress and base 64 encode the strings — Passer By, Jul 24 '17 at 09:38

score 4 · Answer 1 · answered Sep 08 '17 at 07:05

4

These large strings seem more like resources than code, and I would use the resource section of a windows binary (FindResource/LoadResource) and the answer to the SO: embedding resources into linux executable to insert the same data into linux.

answered Sep 08 '17 at 07:05

mksteve

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JazzSoft · Answer 2 · 2017-07-25T21:45:41.773

You can split the text string into multiple strings. Following code worked on Visual Studio 2017:

const char* p1 = "1234567890...";  // Very long (length > 65000)
const char* p2 = "abcdefghij...";  // Very long (length > 65000)
string s = p1;
s += p2;
cout << s.size() << endl;

You have to write the text string in multiple lines like:

const char* p = "This is a "
    "very long string...";

Actually the maximum limit in Visual C++ is 65535. Here is the compiler error message:

fatal error C1091: compiler limit: string exceeds 65535 bytes in length

score 0 · Answer 3 · answered Jul 24 '17 at 11:10

0

Try using an array.

https://msdn.microsoft.com/en-us/library/81k8cwsz.aspx

The maximum size for an array is defined by size_t. Defined in the header file STDDEF.H, size_t is an unsigned int with the range 0x00000000 to 0x7CFFFFFF.

answered Jul 24 '17 at 11:10

The Techel

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Florian Weimer · Answer 4 · 2017-07-24T09:22:24.083

-3

The Microsoft documentation says that using concatenation (i.e., writing "a" "b" "c" instead of "abc") allows you to increase the limit to around 64 KiB bytes. But this is not sufficient for your use case.

If not, you can perhaps save the string separately, convert it to a byte array initializer using xxd -i (xxd comes with [vim](http://www.vim.org/)), and#include` that (but you'll have to add the null terminator manually).

edited Jul 24 '17 at 09:22

answered Jul 24 '17 at 08:42

Florian Weimer

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I've written that the string literals are bigger than 65535 bytes, I'll take a look at the array initializer technique. – MiP Jul 24 '17 at 08:43

Increase string literal length limit

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