Fix #5027: segfault in DComputeSemanticAnalyser::visit(VarDeclaration)#5099
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Codingisinmyblud wants to merge 1 commit intoldc-developers:masterfrom
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Fix #5027: segfault in DComputeSemanticAnalyser::visit(VarDeclaration)#5099Codingisinmyblud wants to merge 1 commit intoldc-developers:masterfrom
Codingisinmyblud wants to merge 1 commit intoldc-developers:masterfrom
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Guard against decl->type being null when semantic analysis encounters VarDeclarations from failed template instantiations in imported modules. When a @compute module imports a template via -I and uses __traits(compiles, ...) to test it, the recursive walker may visit VarDeclaration nodes whose type field is null. The unconditional dereference of decl->type on the check for Taarray/Tclass causes a segmentation fault. Fixes ldc-developers#5027.
Codingisinmyblud
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While looking into this issue I noticed that decl->type can sometimes be null when semantic analysis visits VarDeclarations coming from failed template instantiations in imported modules.
This showed up when a @compute module imports a template via -I and checks it with __traits(compiles, ...). In that case the recursive walker can reach a VarDeclaration whose type was never set, and the code was dereferencing decl->type unconditionally when checking for Taarray/Tclass, which leads to a segfault.
I added a small guard for this case. Let me know if this looks reasonable or if there’s a better way to handle it.
Thank you so much
Fixes #5027.