FEXCore: Fixes circular dependency with thunk callback #5204
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Fixes crash in thunks that use callbacks, introduced in FEX-Emu#5148. The dispatcher would call the syscallhandler to get the VDSO thunk callback. But due to reordering initialization, the VDSO thunk would have not been loaded at that point. This would cause thunks that use callbacks to crash with a nullptr exception. Instead, defer the thunk callback pointer loading until the thread starts executing, and load the pointer in to our thread state's pointer struct instead. Didn't get caught in my initial test sweep since I didn't run a Wine game with thunks.
lioncash
approved these changes
Jan 7, 2026
Contributor
|
Seems like instcountci needs to be updated |
Contributor
|
Oh, nvm, sent the comment right as the PR was updated |
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Fixes crash in thunks that use callbacks, introduced in #5148.
The dispatcher would call the syscallhandler to get the VDSO thunk callback. But due to reordering initialization, the VDSO thunk would have not been loaded at that point. This would cause thunks that use callbacks to crash with a nullptr exception.
Instead, defer the thunk callback pointer loading until the thread starts executing, and load the pointer in to our thread state's pointer struct instead.
Didn't get caught in my initial test sweep since I didn't run a Wine game with thunks.