vlq_base128_le is still incorrectrly compiled in C++

[yav]

Hello,

The problem described in #559 still exists (at least with 0.10 version of the compiler which is what I have). It is not enough to add the cast just at end, because the computation is still done at the wrong type, and we just end up casting the wrong value at the end. You have to cast every single expression as well, have a closer look at the solution proposed by @mikhail-khalizev in #559.

[generalmimon]

main.cpp

#include <iostream>
#include <sstream>
#include "kaitai/kaitaistream.h"
#include "vlq_base128_le.h"

int main() {
    // VlqBase128Le r = new VlqBase128Le(new KaitaiStream(new byte[] {0b1_0111000, 0b1_1100101, 0b1_1001111, 0b1_0101111, 0b0_1101101}));
    std::string str("\xb8\xe5\xcf\xaf\x6d", 5);
    std::istringstream is(str);
    kaitai::kstream ks(&is);

    vlq_base128_le_t r(&ks);

    std::cout << "  Actual value = 0x" << std::hex << r.value() << std::dec << std::endl;
    // 0x6d5f3f2b8 = 0b1101101_0101111_1001111_1100101_0111000
    std::cout << "Expected value = 0x6d5f3f2b8" << std::endl;

    std::cout << "  Actual value_signed = " << r.value_signed() << std::endl;
    std::cout << "Expected value_signed = -5000400200" << std::endl;
}

Dockerfile

FROM gcc:13
COPY main.cpp /usr/src/myapp/
WORKDIR /usr/src/myapp
RUN curl -fsSLO https://github.com/kaitai-io/formats-kaitai-io.github.io/raw/3c8309dd31fef81e66ef3c30f99998d7bd6ac16f/vlq_base128_le/src/cpp_stl_11/vlq_base128_le.{cpp,h}
RUN git clone -b 0.10 --depth 1 https://github.com/kaitai-io/kaitai_struct_cpp_stl_runtime.git
RUN g++ -O1 -std=c++11 -Wall -Wextra -Wpedantic -Wconversion -fsanitize=undefined -o myapp -DKS_STR_ENCODING_NONE -Ikaitai_struct_cpp_stl_runtime kaitai_struct_cpp_stl_runtime/kaitai/kaitaistream.cpp vlq_base128_le.cpp main.cpp
CMD ["./myapp"]

pp@DESKTOP-89OPGF3 MINGW64 /c/temp/ksf-issue-685
$ docker build -t ksf-issue-685 .
[+] Building 0.2s (11/11) FINISHED                                                                                                                                           docker:default
 => [internal] load build definition from Dockerfile                                                                                                                                   0.0s
 => => transferring dockerfile: 593B                                                                                                                                                   0.0s
 => [internal] load .dockerignore                                                                                                                                                      0.0s
 => => transferring context: 2B                                                                                                                                                        0.0s
 => [internal] load metadata for docker.io/library/gcc:13                                                                                                                              0.0s
 => [internal] load build context                                                                                                                                                      0.0s
 => => transferring context: 30B                                                                                                                                                       0.0s
 => [1/6] FROM docker.io/library/gcc:13                                                                                                                                                0.0s
 => CACHED [2/6] COPY main.cpp /usr/src/myapp/                                                                                                                                         0.0s
 => CACHED [3/6] WORKDIR /usr/src/myapp                                                                                                                                                0.0s
 => CACHED [4/6] RUN curl -fsSLO https://github.com/kaitai-io/formats-kaitai-io.github.io/raw/3c8309dd31fef81e66ef3c30f99998d7bd6ac16f/vlq_base128_le/src/cpp_stl_11/vlq_base128_le.{  0.0s
 => CACHED [5/6] RUN git clone -b 0.10 --depth 1 https://github.com/kaitai-io/kaitai_struct_cpp_stl_runtime.git                                                                        0.0s
 => CACHED [6/6] RUN g++ -O1 -std=c++11 -Wall -Wextra -Wpedantic -Wconversion -o myapp -DKS_STR_ENCODING_NONE -Ikaitai_struct_cpp_stl_runtime kaitai_struct_cpp_stl_runtime/kaitai/ka  0.0s
 => exporting to image                                                                                                                                                                 0.0s
 => => exporting layers                                                                                                                                                                0.0s
 => => writing image sha256:4d88eb098539c456e7bacfe4af5903322e5b3351ff757a49e92a23fab424de03                                                                                           0.0s
 => => naming to docker.io/library/ksf-issue-685                                                                                                                                       0.0s

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pp@DESKTOP-89OPGF3 MINGW64 /c/temp/ksf-issue-685
$ docker run -it --rm ksf-issue-685
  Actual value = 0x6d5f3f2b8
Expected value = 0x6d5f3f2b8
  Actual value_signed = -5000400200
Expected value_signed = -5000400200