Fix generator output for functions with a parameter named ret - #184
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Fix generator output for functions with a parameter named ret#184rootkiller6788 wants to merge 1 commit into
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The return value slot of a generated wrapper function was named `v_ret_`, which collides with the local copy of a parameter named `ret` (parameter locals are built as `v_<name>_`, so `ret` becomes `v_ret_`). The generated code then declared `v_ret_` twice in the same scope, e.g. for libxslt functions that use `ret` as a parameter name. Rename the return value variable to `v_ret`, which cannot collide with any parameter-derived variable since those always carry a trailing underscore. Fixes google#142
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Fixes #142: the clang generator emits syntactically invalid wrapper code when a sandboxed function has a parameter named
ret.The client-side wrapper generated by
Emitter::DoEmitFunction()declares the return-value slot asv_ret_and the local copy of each parameter asv_<name>_. For a parameter namedret, both variables end up namedv_ret_in the same scope, so the generated header does not compile ("redeclaration of 'v_ret_'"). This breaks headers like libxslt's that useretas a parameter name.This change renames the return-value slot to
v_ret. Parameter-derived variables always carry a trailing underscore, sov_retcan never collide with them.Verified by compiling the generated wrapper for
int FunctionWithRet(int ret)with g++: before the fix it fails witherror: redeclaration of 'sapi::v::Int v_ret_'; after the fix it compiles cleanly. A regression test (EmitterTest.ParameterNamedRet) checks that the return slot and the parameter copy are passed tosandbox_->Call()as two distinct variables.