Fix reserve pitfall in printString#14835
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xokdvium merged 1 commit intoNixOS:masterfrom Dec 19, 2025
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Remove the per-call reserve() inside printString to avoid linear-growth reallocations when called in loops (e.g. printStrings). Derivation::unparse already pre-reserves a large buffer, so this remains efficient while preserving amortized growth behavior when the initial estimate is exceeded.
xokdvium
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Dec 19, 2025
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Indeed. We should just rely on exponential growth for this.
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Remove the per-call reserve() inside printString to avoid linear-growth reallocations when called in loops (e.g. printStrings). Derivation::unparse already pre-reserves a large buffer, so this remains efficient while preserving amortized growth behavior when the initial estimate is exceeded.
Motivation
#14823 (comment)
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