Conditional allocations shouldn't fail for size=0 in C++ backend (#7255) #7256
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Allocations can be conditional; if the condition evaluates to false, we end up calling `halide_malloc(0)` (or `halide_tcm_malloc(0)` in the xtensa branch). Since it's legal via spec for `malloc(0)` to return nullptr, we need to be cautious here: if we are compiling with assertions enabled, *and* have a malloc() (etc) implementation that returns nullptr for alloc(0), we need to skip the assertion check, since we know the result won't be used. Note: a similar check will be inserted in the xtensa branch separately. Note 2: LLVM backend already has this check via Codegen_Posix.cpp
abadams
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ardier
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…ide#7255) (halide#7256) * Conditional allocations shouldn't fail for size=0 in C++ backend (halide#7255) Allocations can be conditional; if the condition evaluates to false, we end up calling `halide_malloc(0)` (or `halide_tcm_malloc(0)` in the xtensa branch). Since it's legal via spec for `malloc(0)` to return nullptr, we need to be cautious here: if we are compiling with assertions enabled, *and* have a malloc() (etc) implementation that returns nullptr for alloc(0), we need to skip the assertion check, since we know the result won't be used. Note: a similar check will be inserted in the xtensa branch separately. Note 2: LLVM backend already has this check via Codegen_Posix.cpp * Update CodeGen_C.cpp
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Allocations can be conditional; if the condition evaluates to false, we end up calling
halide_malloc(0)(orhalide_tcm_malloc(0)in the xtensa branch). Since it's legal via spec formalloc(0)to return nullptr, we need to be cautious here: if we are compiling with assertions enabled, and have a malloc() (etc) implementation that returns nullptr for alloc(0), we need to skip the assertion check, since we know the result won't be used.Note: a similar check will be inserted in the xtensa branch separately.
Note 2: LLVM backend already has this check via Codegen_Posix.cpp