Fixed a bug that occurred when compiling with the clang18 compiler.

Signed-off-by: Hao Chen <[email protected]>

This fixes opencv#26011

Disable strict mode when reading avif files

videoio: fix V4L backend with NV12 input format

Workaround for division by zero, issue opencv#25795

…ffset

Added offset for HAL as ofs2idx expects 1-based index opencv#26080

### Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [ ] The PR is proposed to the proper branch
- [ ] There is a reference to the original bug report and related work
- [ ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
      Patch to opencv_extra has the same branch name.
- [ ] The feature is well documented and sample code can be built with the project CMake

Resolve compilation bug on LoongArch platform

Fix link for "RANSAC for Dummies" tutorial.

Got rid of CAROTENE_NEON_ARCH and use standard __ARM_ARCH check

Fix typo with cameramatrix command for documentation

Update test_tiff.cpp opencv#26093

related opencv#22090

### Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch
- [x] There is a reference to the original bug report and related work
- [x] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
      Patch to opencv_extra has the same branch name.
- [ ] The feature is well documented and sample code can be built with the project CMake

Make T a math symbol

Remove the redundant codes of cv::convertMaps and mRGBA2RGBA<uchar> opencv#26071

(1) cv::convertMaps: the branch [else if( m1type == CV_32FC2 && dstm1type == CV_16SC2 ) if( nninterpolate )] is unreachable,
    as the condition is satisfied in lines 1959 to 1961, calculated in advance and return directly.
(2) mRGBA2RGBA<uchar>: dst[0], dst[1], dst[2] and dst[3] is calculated repeatedly. Introduced in opencv#13440

### Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [ ] I agree to contribute to the project under Apache 2 License.
- [ ] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [ ] The PR is proposed to the proper branch
- [ ] There is a reference to the original bug report and related work
- [ ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
      Patch to opencv_extra has the same branch name.
- [ ] The feature is well documented and sample code can be built with the project CMake

Avoid uninitialized value read in resize. opencv#26084

When there is no point falling right, an hypothetical value is computed (but unused) using an uninitialized ofst. This triggers warnings in the sanitizers.

Including those values in the for loops is also possible but messy when SIMD is involved.

### Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch

build: minor changes for cmake 3.30 and some cleanup

Added bit-exact tests for RGB2Gray

- Make x a math symbol
- Fix a typo

RISC-V: remove statically initialized global RVV variables (4.x)

Added more data types to OCL flip() and rotate() perf tests opencv#26115

Connected PR with updated sanity data: opencv/opencv_extra#1206

### Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch
- [ ] There is a reference to the original bug report and related work
- [x] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
      Patch to opencv_extra has the same branch name.
- [x] The feature is well documented and sample code can be built with the project CMake

Update remap tutorial

Excluded nullptr leak to arithmetic HAL got from empty Mat.

Add size() to CUDA PtrStepSz opencv#26042

According to [cppreference.com compiler support table](https://en.cppreference.com/w/cpp/compiler_support/17), `nvcc` supports `[[nodiscard]]` from version 11.

### Pull Request Readiness Checklist

See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request

- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch
- [ ] There is a reference to the original bug report and related work
- [ ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
      Patch to opencv_extra has the same branch name.
- [ ] The feature is well documented and sample code can be built with the project CMake

Related: opencv#25659