QT6 cannot build icu by cmake.

[HeisenbergChen114]

Description / Steps to reproduce the issue

There is a issue on build program using qt6.I installed msys2 on windows10, and setup mingw64 tools-chain and mingw_x86 icu. But when i tried to build a qt6 program with including <unicode/ucsdet.h>. There's some error on building program. What's wrong with it?

Expected behavior

// my code for testing icu working properly
#include "icu_lib.h"
#include <unicode/ucsdet.h>
#include <iostream>
Icu_lib::Icu_lib(QWidget *parent)
    : QWidget{parent}
{}

void Icu_lib::runIcu()
{




    const char *text = "Hello, 世界!";
    char *detected = nullptr;
    if (detectTextEncoding(text, strlen(text), &detected)) {
        std::cout << "Detected encoding: " << detected << std::endl;
        free(detected);
    } else {
        std::cout << "Failed to detect encoding." << std::endl;
    }
    return ;

}

bool Icu_lib::detectTextEncoding(const char *data, int32_t len, char **detected)
{
    UErrorCode status = U_ZERO_ERROR;
    UCharsetDetector *csd = ucsdet_open(&status);
    if (U_FAILURE(status)) return false;

    ucsdet_setText(csd, data, len, &status);
    if (U_FAILURE(status)) return false;

    int32_t matchCount = 0;
    const UCharsetMatch **csm = ucsdet_detectAll(csd, &matchCount, &status);
    if (U_FAILURE(status)) return false;

    if (matchCount > 0) {
        *detected = strdup(ucsdet_getName(csm[0], &status));
        if (U_FAILURE(status)) return false;
    }

    ucsdet_close(csd);
    return true;
}

Actual behavior

C:\Users\WIN10\Documents\icu_test\icu_lib.cpp:-1: error: undefined reference to ucsdet_open_77' :-1: error: C:/Users/WIN10/Documents/icu_test/icu_lib.cpp:32:(.text+0x1a1): undefined reference to ucsdet_setText_77'
👎 error: C:/Users/WIN10/Documents/icu_test/icu_lib.cpp:36:(.text+0x1dc): undefined reference to ucsdet_detectAll_77' :-1: error: C:/Users/WIN10/Documents/icu_test/icu_lib.cpp:40:(.text+0x214): undefined reference to ucsdet_getName_77'
👎 error: C:/Users/WIN10/Documents/icu_test/icu_lib.cpp:44:(.text+0x24c): undefined reference to `ucsdet_close_77'
👎 error: collect2.exe: error: ld returned 1 exit status
👎 error: ninja: build stopped: subcommand failed.

Verification

• I have verified that my MSYS2 is up-to-date before submitting the report (see https://www.msys2.org/docs/updating/)

Windows Version

win10

MINGW environments affected

• MINGW64
• MINGW32
• UCRT64
• CLANG64
• CLANGARM64

Are you willing to submit a PR?

No response

[mmuetzel]

That is probably because the symbols of their C API aren't exported from the shared libraries on MinGW.

Could you please check with the build artifacts of #24495 (when they are ready) if that resolves your issue?