Pass LargeDataThreshold to LLVM module IR - #161670
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Before, LargeDataThreshold was only set via `LLVMRustCreateTargetMachine`. When LTO is enabled, this information is required to be passed into the generated LLVM module IR files since the LTO linker spins up its own TargetMachine and otherwise has no knowledge of the LargeDataThreshold. Currently, `-Z large-data-threshold` has no affect at all when compiling with LTO. This commit makes sure that if `-Z large-data-threshold` is passed and not 0, it is preserved and stored into the generated LLVM IR.
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nagisa
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Previously, the code unwrapped large_data_threshold with a default of 0 and sets it in the LLVM module if it is != 0. Instead, we should simply check if large_data_threshold has a value.
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…nagisa Pass LargeDataThreshold to LLVM module IR Before, LargeDataThreshold was only set via `LLVMRustCreateTargetMachine`. When LTO is enabled, this information is required to be passed into the generated LLVM module IR files since the LTO linker spins up its own TargetMachine and otherwise has no knowledge of the LargeDataThreshold. Currently, `-Z large-data-threshold` has no affect at all when compiling with LTO. This commit makes sure that if `-Z large-data-threshold` is passed and not 0, it is preserved and stored into the generated LLVM IR.
This was referenced Aug 24, 2026
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Rollup of 9 pull requests Successful merges: - #161689 (bootstrap: don't LTO C dependencies on aarch64) - #161553 (rustdoc: fix issue preventing "read more" links from generating.) - #161670 (Pass LargeDataThreshold to LLVM module IR) - #146529 (rustdoc: Nuke `--passes=list` and defossilize the passes infrastructure) - #156009 (Check `redundant_explicit_links` against generated URLs) - #159583 (Add new `invalid_markdown_table` rustdoc lint) - #161098 (PassWrapper: handle LLVM 24 change in function types) - #161641 (Check for missing rustfmt in the stdarch intrinsic test step sooner) - #161661 (Don't treat slashes as path seps after drive letters in verbatim paths) Failed merges: - #156749 (remove `box_patterns`)
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Rollup merge of #161670 - jakos-sec:large-data-threshold, r=nagisa Pass LargeDataThreshold to LLVM module IR Before, LargeDataThreshold was only set via `LLVMRustCreateTargetMachine`. When LTO is enabled, this information is required to be passed into the generated LLVM module IR files since the LTO linker spins up its own TargetMachine and otherwise has no knowledge of the LargeDataThreshold. Currently, `-Z large-data-threshold` has no affect at all when compiling with LTO. This commit makes sure that if `-Z large-data-threshold` is passed and not 0, it is preserved and stored into the generated LLVM IR.
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Before, LargeDataThreshold was only set via
LLVMRustCreateTargetMachine. When LTO is enabled, this information is required to be passed into the generated LLVM module IR files since the LTO linker spins up its own TargetMachine and otherwise has no knowledge of the LargeDataThreshold.Currently,
-Z large-data-thresholdhas no affect at all when compiling with LTO.This commit makes sure that if
-Z large-data-thresholdis passed and not 0, it is preserved and stored into the generated LLVM IR.