Set C++17 standard for WebAssembly target

[Copilot]

Emscripten's embind now requires C++17, but the build inherited C++11 from the root CMakeLists.txt, causing compilation failure.

Changes

Added target-specific C++17 requirement in wasm/CMakeLists.txt:

set_target_properties(dicomiccwasm PROPERTIES
    CXX_STANDARD 17
    CXX_STANDARD_REQUIRED ON
)

This overrides the inherited C++11 standard for the WebAssembly target only, leaving other build configurations unchanged.

Original prompt

Problem

The WebAssembly build is failing with the error:

error: "embind requires -std=c++17 or newer"

This occurs when building wasm/CMakeFiles/dicomiccwasm.dir/src/jslib.cpp.o because Emscripten's embind library now requires C++17 or newer, but the current build configuration doesn't specify a C++ standard.

Solution

Update the wasm/CMakeLists.txt file to set the C++ standard to C++17 for the dicomiccwasm target.

Add the following lines after the add_executable(dicomiccwasm src/jslib.cpp) line:

set_target_properties(dicomiccwasm PROPERTIES
    CXX_STANDARD 17
    CXX_STANDARD_REQUIRED ON
)

Or alternatively, you can set it globally for the wasm directory by adding at the top of wasm/CMakeLists.txt:

set(CMAKE_CXX_STANDARD 17)
set(CMAKE_CXX_STANDARD_REQUIRED ON)

Reference

• Failing job: https://github.com/ImagingDataCommons/libdicomicc/actions/runs/21632149111/job/62347442910
• Error occurs at commit: 26a69ab
• File to modify: wasm/CMakeLists.txt

This pull request was created from Copilot chat.

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