COMP: Fix ill-formed std::abs<double> in ConditionalMedianImageFilter#975
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hjmjohnson wants to merge 1 commit into
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COMP: Fix ill-formed std::abs<double> in ConditionalMedianImageFilter#975hjmjohnson wants to merge 1 commit into
hjmjohnson wants to merge 1 commit into
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std::abs has no function-template overload accepting an explicit template argument, so std::abs<double>(x) is ill-formed and rejected as an ambiguous call by conforming compilers (e.g. Apple clang). Compute the difference in double and call the unambiguous std::abs(double) overload.
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July 23, 2026 01:42
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std::abshas no function-template overload that accepts an explicit template argument, sostd::abs<double>(x)is ill-formed. Conforming compilers (e.g. Apple clang) reject it as an ambiguous call, breaking any consumer that instantiatesConditionalMedianImageFilter. This computes the difference indoubleand calls the unambiguousstd::abs(double)overload.Context
Introduced by commit
3936486("COMP: Drop use of itk::Math::Absolute to fix compilation warnings"), which replaceditk::Math::Absolute(...)withstd::abs<double>(...). The surrounding arithmetic (sum,mean,stdev) is already computed indouble, so casting the pixel-difference todoubleand callingstd::abs(double)matches the intended semantics and remains warning-free.Discovered while building RTK as an ITK remote module with Apple clang, where every translation unit including
rtkConditionalMedianImageFilter.hxxfailed withcall to 'abs' is ambiguous. Verified locally: rebuilt RTK application/test targets with this change; the errors are cleared.