| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `crates/hir-ty/src/next_solver/fulfill.rs`."><title>fulfill.rs - source</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-6b053e98.ttf.woff2,FiraSans-Italic-81dc35de.woff2,FiraSans-Regular-0fe48ade.woff2,FiraSans-MediumItalic-ccf7e434.woff2,FiraSans-Medium-e1aa3f0a.woff2,SourceCodePro-Regular-8badfe75.ttf.woff2,SourceCodePro-Semibold-aa29a496.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2"href="../../../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../../../static.files/normalize-9960930a.css"><link rel="stylesheet" href="../../../static.files/rustdoc-e56847b5.css"><meta name="rustdoc-vars" data-root-path="../../../" data-static-root-path="../../../static.files/" data-current-crate="hir_ty" data-themes="" data-resource-suffix="" data-rustdoc-version="1.91.1 (ed61e7d7e 2025-11-07)" data-channel="1.91.1" data-search-js="search-e256b49e.js" data-stringdex-js="stringdex-c3e638e9.js" data-settings-js="settings-c38705f0.js" ><script src="../../../static.files/storage-e2aeef58.js"></script><script defer src="../../../static.files/src-script-813739b1.js"></script><script defer src="../../../src-files.js"></script><script defer src="../../../static.files/main-6dc2a7f3.js"></script><noscript><link rel="stylesheet" href="../../../static.files/noscript-263c88ec.css"></noscript><link rel="alternate icon" type="image/png" href="../../../static.files/favicon-32x32-eab170b8.png"><link rel="icon" type="image/svg+xml" href="../../../static.files/favicon-044be391.svg"></head><body class="rustdoc src"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="src-sidebar-title"><h2>Files</h2></div></nav><div class="sidebar-resizer" title="Drag to resize sidebar"></div><main><section id="main-content" class="content"><div class="main-heading"><h1><div class="sub-heading">hir_ty/next_solver/</div>fulfill.rs</h1><rustdoc-toolbar></rustdoc-toolbar></div><div class="example-wrap digits-3"><pre class="rust"><code><a href=#1 id=1 data-nosnippet>1</a><span class="doccomment">//! Fulfill loop for next-solver. |
| <a href=#2 id=2 data-nosnippet>2</a> |
| <a href=#3 id=3 data-nosnippet>3</a></span><span class="kw">mod </span>errors; |
| <a href=#4 id=4 data-nosnippet>4</a> |
| <a href=#5 id=5 data-nosnippet>5</a><span class="kw">use </span>std::ops::ControlFlow; |
| <a href=#6 id=6 data-nosnippet>6</a> |
| <a href=#7 id=7 data-nosnippet>7</a><span class="kw">use </span>rustc_hash::FxHashSet; |
| <a href=#8 id=8 data-nosnippet>8</a><span class="kw">use </span>rustc_next_trait_solver::{ |
| <a href=#9 id=9 data-nosnippet>9</a> delegate::SolverDelegate, |
| <a href=#10 id=10 data-nosnippet>10</a> solve::{GoalEvaluation, GoalStalledOn, HasChanged, SolverDelegateEvalExt}, |
| <a href=#11 id=11 data-nosnippet>11</a>}; |
| <a href=#12 id=12 data-nosnippet>12</a><span class="kw">use </span>rustc_type_ir::{ |
| <a href=#13 id=13 data-nosnippet>13</a> Interner, TypeSuperVisitable, TypeVisitable, TypeVisitableExt, TypeVisitor, |
| <a href=#14 id=14 data-nosnippet>14</a> inherent::{IntoKind, Span <span class="kw">as _</span>}, |
| <a href=#15 id=15 data-nosnippet>15</a> solve::{Certainty, NoSolution}, |
| <a href=#16 id=16 data-nosnippet>16</a>}; |
| <a href=#17 id=17 data-nosnippet>17</a> |
| <a href=#18 id=18 data-nosnippet>18</a><span class="kw">use </span><span class="kw">crate</span>::next_solver::{ |
| <a href=#19 id=19 data-nosnippet>19</a> DbInterner, SolverContext, SolverDefId, Span, Ty, TyKind, TypingMode, |
| <a href=#20 id=20 data-nosnippet>20</a> infer::{ |
| <a href=#21 id=21 data-nosnippet>21</a> InferCtxt, |
| <a href=#22 id=22 data-nosnippet>22</a> traits::{PredicateObligation, PredicateObligations}, |
| <a href=#23 id=23 data-nosnippet>23</a> }, |
| <a href=#24 id=24 data-nosnippet>24</a> inspect::ProofTreeVisitor, |
| <a href=#25 id=25 data-nosnippet>25</a>}; |
| <a href=#26 id=26 data-nosnippet>26</a> |
| <a href=#27 id=27 data-nosnippet>27</a><span class="kw">type </span>PendingObligations<<span class="lifetime">'db</span>> = |
| <a href=#28 id=28 data-nosnippet>28</a> Vec<(PredicateObligation<<span class="lifetime">'db</span>>, <span class="prelude-ty">Option</span><GoalStalledOn<DbInterner<<span class="lifetime">'db</span>>>>)>; |
| <a href=#29 id=29 data-nosnippet>29</a> |
| <a href=#30 id=30 data-nosnippet>30</a><span class="doccomment">/// A trait engine using the new trait solver. |
| <a href=#31 id=31 data-nosnippet>31</a>/// |
| <a href=#32 id=32 data-nosnippet>32</a>/// This is mostly identical to how `evaluate_all` works inside of the |
| <a href=#33 id=33 data-nosnippet>33</a>/// solver, except that the requirements are slightly different. |
| <a href=#34 id=34 data-nosnippet>34</a>/// |
| <a href=#35 id=35 data-nosnippet>35</a>/// Unlike `evaluate_all` it is possible to add new obligations later on |
| <a href=#36 id=36 data-nosnippet>36</a>/// and we also have to track diagnostics information by using `Obligation` |
| <a href=#37 id=37 data-nosnippet>37</a>/// instead of `Goal`. |
| <a href=#38 id=38 data-nosnippet>38</a>/// |
| <a href=#39 id=39 data-nosnippet>39</a>/// It is also likely that we want to use slightly different datastructures |
| <a href=#40 id=40 data-nosnippet>40</a>/// here as this will have to deal with far more root goals than `evaluate_all`. |
| <a href=#41 id=41 data-nosnippet>41</a></span><span class="attr">#[derive(Debug, Clone)] |
| <a href=#42 id=42 data-nosnippet>42</a></span><span class="kw">pub struct </span>FulfillmentCtxt<<span class="lifetime">'db</span>> { |
| <a href=#43 id=43 data-nosnippet>43</a> obligations: ObligationStorage<<span class="lifetime">'db</span>>, |
| <a href=#44 id=44 data-nosnippet>44</a> |
| <a href=#45 id=45 data-nosnippet>45</a> <span class="doccomment">/// The snapshot in which this context was created. Using the context |
| <a href=#46 id=46 data-nosnippet>46</a> /// outside of this snapshot leads to subtle bugs if the snapshot |
| <a href=#47 id=47 data-nosnippet>47</a> /// gets rolled back. Because of this we explicitly check that we only |
| <a href=#48 id=48 data-nosnippet>48</a> /// use the context in exactly this snapshot. |
| <a href=#49 id=49 data-nosnippet>49</a> </span><span class="attr">#[expect(unused)] |
| <a href=#50 id=50 data-nosnippet>50</a> </span>usable_in_snapshot: usize, |
| <a href=#51 id=51 data-nosnippet>51</a>} |
| <a href=#52 id=52 data-nosnippet>52</a> |
| <a href=#53 id=53 data-nosnippet>53</a><span class="attr">#[derive(Default, Debug, Clone)] |
| <a href=#54 id=54 data-nosnippet>54</a></span><span class="kw">struct </span>ObligationStorage<<span class="lifetime">'db</span>> { |
| <a href=#55 id=55 data-nosnippet>55</a> <span class="doccomment">/// Obligations which resulted in an overflow in fulfillment itself. |
| <a href=#56 id=56 data-nosnippet>56</a> /// |
| <a href=#57 id=57 data-nosnippet>57</a> /// We cannot eagerly return these as error so we instead store them here |
| <a href=#58 id=58 data-nosnippet>58</a> /// to avoid recomputing them each time `try_evaluate_obligations` is called. |
| <a href=#59 id=59 data-nosnippet>59</a> /// This also allows us to return the correct `FulfillmentError` for them. |
| <a href=#60 id=60 data-nosnippet>60</a> </span>overflowed: Vec<PredicateObligation<<span class="lifetime">'db</span>>>, |
| <a href=#61 id=61 data-nosnippet>61</a> pending: PendingObligations<<span class="lifetime">'db</span>>, |
| <a href=#62 id=62 data-nosnippet>62</a>} |
| <a href=#63 id=63 data-nosnippet>63</a> |
| <a href=#64 id=64 data-nosnippet>64</a><span class="kw">impl</span><<span class="lifetime">'db</span>> ObligationStorage<<span class="lifetime">'db</span>> { |
| <a href=#65 id=65 data-nosnippet>65</a> <span class="kw">fn </span>register( |
| <a href=#66 id=66 data-nosnippet>66</a> <span class="kw-2">&mut </span><span class="self">self</span>, |
| <a href=#67 id=67 data-nosnippet>67</a> obligation: PredicateObligation<<span class="lifetime">'db</span>>, |
| <a href=#68 id=68 data-nosnippet>68</a> stalled_on: <span class="prelude-ty">Option</span><GoalStalledOn<DbInterner<<span class="lifetime">'db</span>>>>, |
| <a href=#69 id=69 data-nosnippet>69</a> ) { |
| <a href=#70 id=70 data-nosnippet>70</a> <span class="self">self</span>.pending.push((obligation, stalled_on)); |
| <a href=#71 id=71 data-nosnippet>71</a> } |
| <a href=#72 id=72 data-nosnippet>72</a> |
| <a href=#73 id=73 data-nosnippet>73</a> <span class="kw">fn </span>clone_pending(<span class="kw-2">&</span><span class="self">self</span>) -> PredicateObligations<<span class="lifetime">'db</span>> { |
| <a href=#74 id=74 data-nosnippet>74</a> <span class="kw">let </span><span class="kw-2">mut </span>obligations: PredicateObligations<<span class="lifetime">'db</span>> = |
| <a href=#75 id=75 data-nosnippet>75</a> <span class="self">self</span>.pending.iter().map(|(o, <span class="kw">_</span>)| o.clone()).collect(); |
| <a href=#76 id=76 data-nosnippet>76</a> obligations.extend(<span class="self">self</span>.overflowed.iter().cloned()); |
| <a href=#77 id=77 data-nosnippet>77</a> obligations |
| <a href=#78 id=78 data-nosnippet>78</a> } |
| <a href=#79 id=79 data-nosnippet>79</a> |
| <a href=#80 id=80 data-nosnippet>80</a> <span class="kw">fn </span>drain_pending<<span class="lifetime">'this</span>, <span class="lifetime">'cond</span>>( |
| <a href=#81 id=81 data-nosnippet>81</a> <span class="kw-2">&</span><span class="lifetime">'this </span><span class="kw-2">mut </span><span class="self">self</span>, |
| <a href=#82 id=82 data-nosnippet>82</a> cond: <span class="kw">impl </span><span class="lifetime">'cond </span>+ Fn(<span class="kw-2">&</span>PredicateObligation<<span class="lifetime">'db</span>>) -> bool, |
| <a href=#83 id=83 data-nosnippet>83</a> ) -> <span class="kw">impl </span>Iterator<Item = (PredicateObligation<<span class="lifetime">'db</span>>, <span class="prelude-ty">Option</span><GoalStalledOn<DbInterner<<span class="lifetime">'db</span>>>>)> |
| <a href=#84 id=84 data-nosnippet>84</a> { |
| <a href=#85 id=85 data-nosnippet>85</a> <span class="self">self</span>.pending.extract_if(.., <span class="kw">move </span>|(o, <span class="kw">_</span>)| cond(o)) |
| <a href=#86 id=86 data-nosnippet>86</a> } |
| <a href=#87 id=87 data-nosnippet>87</a> |
| <a href=#88 id=88 data-nosnippet>88</a> <span class="kw">fn </span>on_fulfillment_overflow(<span class="kw-2">&mut </span><span class="self">self</span>, infcx: <span class="kw-2">&</span>InferCtxt<<span class="lifetime">'db</span>>) { |
| <a href=#89 id=89 data-nosnippet>89</a> infcx.probe(|<span class="kw">_</span>| { |
| <a href=#90 id=90 data-nosnippet>90</a> <span class="comment">// IMPORTANT: we must not use solve any inference variables in the obligations |
| <a href=#91 id=91 data-nosnippet>91</a> // as this is all happening inside of a probe. We use a probe to make sure |
| <a href=#92 id=92 data-nosnippet>92</a> // we get all obligations involved in the overflow. We pretty much check: if |
| <a href=#93 id=93 data-nosnippet>93</a> // we were to do another step of `try_evaluate_obligations`, which goals would |
| <a href=#94 id=94 data-nosnippet>94</a> // change. |
| <a href=#95 id=95 data-nosnippet>95</a> // FIXME: <https://github.com/Gankra/thin-vec/pull/66> is merged, this can be removed. |
| <a href=#96 id=96 data-nosnippet>96</a> </span><span class="self">self</span>.overflowed.extend( |
| <a href=#97 id=97 data-nosnippet>97</a> <span class="self">self</span>.pending |
| <a href=#98 id=98 data-nosnippet>98</a> .extract_if(.., |(o, stalled_on)| { |
| <a href=#99 id=99 data-nosnippet>99</a> <span class="kw">let </span>goal = o.as_goal(); |
| <a href=#100 id=100 data-nosnippet>100</a> <span class="kw">let </span>result = <<span class="kw-2">&</span>SolverContext<<span class="lifetime">'db</span>>>::from(infcx).evaluate_root_goal( |
| <a href=#101 id=101 data-nosnippet>101</a> goal, |
| <a href=#102 id=102 data-nosnippet>102</a> Span::dummy(), |
| <a href=#103 id=103 data-nosnippet>103</a> stalled_on.take(), |
| <a href=#104 id=104 data-nosnippet>104</a> ); |
| <a href=#105 id=105 data-nosnippet>105</a> <span class="macro">matches!</span>(result, <span class="prelude-val">Ok</span>(GoalEvaluation { has_changed: HasChanged::Yes, .. })) |
| <a href=#106 id=106 data-nosnippet>106</a> }) |
| <a href=#107 id=107 data-nosnippet>107</a> .map(|(o, <span class="kw">_</span>)| o), |
| <a href=#108 id=108 data-nosnippet>108</a> ); |
| <a href=#109 id=109 data-nosnippet>109</a> }) |
| <a href=#110 id=110 data-nosnippet>110</a> } |
| <a href=#111 id=111 data-nosnippet>111</a>} |
| <a href=#112 id=112 data-nosnippet>112</a> |
| <a href=#113 id=113 data-nosnippet>113</a><span class="kw">impl</span><<span class="lifetime">'db</span>> FulfillmentCtxt<<span class="lifetime">'db</span>> { |
| <a href=#114 id=114 data-nosnippet>114</a> <span class="kw">pub fn </span>new(infcx: <span class="kw-2">&</span>InferCtxt<<span class="lifetime">'db</span>>) -> FulfillmentCtxt<<span class="lifetime">'db</span>> { |
| <a href=#115 id=115 data-nosnippet>115</a> FulfillmentCtxt { |
| <a href=#116 id=116 data-nosnippet>116</a> obligations: Default::default(), |
| <a href=#117 id=117 data-nosnippet>117</a> usable_in_snapshot: infcx.num_open_snapshots(), |
| <a href=#118 id=118 data-nosnippet>118</a> } |
| <a href=#119 id=119 data-nosnippet>119</a> } |
| <a href=#120 id=120 data-nosnippet>120</a>} |
| <a href=#121 id=121 data-nosnippet>121</a> |
| <a href=#122 id=122 data-nosnippet>122</a><span class="kw">impl</span><<span class="lifetime">'db</span>> FulfillmentCtxt<<span class="lifetime">'db</span>> { |
| <a href=#123 id=123 data-nosnippet>123</a> <span class="attr">#[tracing::instrument(level = <span class="string">"trace"</span>, skip(<span class="self">self</span>, _infcx))] |
| <a href=#124 id=124 data-nosnippet>124</a> </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>register_predicate_obligation( |
| <a href=#125 id=125 data-nosnippet>125</a> <span class="kw-2">&mut </span><span class="self">self</span>, |
| <a href=#126 id=126 data-nosnippet>126</a> _infcx: <span class="kw-2">&</span>InferCtxt<<span class="lifetime">'db</span>>, |
| <a href=#127 id=127 data-nosnippet>127</a> obligation: PredicateObligation<<span class="lifetime">'db</span>>, |
| <a href=#128 id=128 data-nosnippet>128</a> ) { |
| <a href=#129 id=129 data-nosnippet>129</a> <span class="comment">// FIXME: See the comment in `try_evaluate_obligations()`. |
| <a href=#130 id=130 data-nosnippet>130</a> // assert_eq!(self.usable_in_snapshot, infcx.num_open_snapshots()); |
| <a href=#131 id=131 data-nosnippet>131</a> </span><span class="self">self</span>.obligations.register(obligation, <span class="prelude-val">None</span>); |
| <a href=#132 id=132 data-nosnippet>132</a> } |
| <a href=#133 id=133 data-nosnippet>133</a> |
| <a href=#134 id=134 data-nosnippet>134</a> <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>register_predicate_obligations( |
| <a href=#135 id=135 data-nosnippet>135</a> <span class="kw-2">&mut </span><span class="self">self</span>, |
| <a href=#136 id=136 data-nosnippet>136</a> _infcx: <span class="kw-2">&</span>InferCtxt<<span class="lifetime">'db</span>>, |
| <a href=#137 id=137 data-nosnippet>137</a> obligations: <span class="kw">impl </span>IntoIterator<Item = PredicateObligation<<span class="lifetime">'db</span>>>, |
| <a href=#138 id=138 data-nosnippet>138</a> ) { |
| <a href=#139 id=139 data-nosnippet>139</a> <span class="comment">// FIXME: See the comment in `try_evaluate_obligations()`. |
| <a href=#140 id=140 data-nosnippet>140</a> // assert_eq!(self.usable_in_snapshot, infcx.num_open_snapshots()); |
| <a href=#141 id=141 data-nosnippet>141</a> </span>obligations.into_iter().for_each(|obligation| <span class="self">self</span>.obligations.register(obligation, <span class="prelude-val">None</span>)); |
| <a href=#142 id=142 data-nosnippet>142</a> } |
| <a href=#143 id=143 data-nosnippet>143</a> |
| <a href=#144 id=144 data-nosnippet>144</a> <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>collect_remaining_errors( |
| <a href=#145 id=145 data-nosnippet>145</a> <span class="kw-2">&mut </span><span class="self">self</span>, |
| <a href=#146 id=146 data-nosnippet>146</a> _infcx: <span class="kw-2">&</span>InferCtxt<<span class="lifetime">'db</span>>, |
| <a href=#147 id=147 data-nosnippet>147</a> ) -> Vec<NextSolverError<<span class="lifetime">'db</span>>> { |
| <a href=#148 id=148 data-nosnippet>148</a> <span class="self">self</span>.obligations |
| <a href=#149 id=149 data-nosnippet>149</a> .pending |
| <a href=#150 id=150 data-nosnippet>150</a> .drain(..) |
| <a href=#151 id=151 data-nosnippet>151</a> .map(|(obligation, <span class="kw">_</span>)| NextSolverError::Ambiguity(obligation)) |
| <a href=#152 id=152 data-nosnippet>152</a> .chain(<span class="self">self</span>.obligations.overflowed.drain(..).map(NextSolverError::Overflow)) |
| <a href=#153 id=153 data-nosnippet>153</a> .collect() |
| <a href=#154 id=154 data-nosnippet>154</a> } |
| <a href=#155 id=155 data-nosnippet>155</a> |
| <a href=#156 id=156 data-nosnippet>156</a> <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>try_evaluate_obligations( |
| <a href=#157 id=157 data-nosnippet>157</a> <span class="kw-2">&mut </span><span class="self">self</span>, |
| <a href=#158 id=158 data-nosnippet>158</a> infcx: <span class="kw-2">&</span>InferCtxt<<span class="lifetime">'db</span>>, |
| <a href=#159 id=159 data-nosnippet>159</a> ) -> Vec<NextSolverError<<span class="lifetime">'db</span>>> { |
| <a href=#160 id=160 data-nosnippet>160</a> <span class="comment">// FIXME(next-solver): We should bring this assertion back. Currently it panics because |
| <a href=#161 id=161 data-nosnippet>161</a> // there are places which use `InferenceTable` and open a snapshot and register obligations |
| <a href=#162 id=162 data-nosnippet>162</a> // and select. They should use a different `ObligationCtxt` instead. Then we'll be also able |
| <a href=#163 id=163 data-nosnippet>163</a> // to not put the obligations queue in `InferenceTable`'s snapshots. |
| <a href=#164 id=164 data-nosnippet>164</a> // assert_eq!(self.usable_in_snapshot, infcx.num_open_snapshots()); |
| <a href=#165 id=165 data-nosnippet>165</a> </span><span class="kw">let </span><span class="kw-2">mut </span>errors = Vec::new(); |
| <a href=#166 id=166 data-nosnippet>166</a> <span class="kw">let </span><span class="kw-2">mut </span>obligations = Vec::new(); |
| <a href=#167 id=167 data-nosnippet>167</a> <span class="kw">loop </span>{ |
| <a href=#168 id=168 data-nosnippet>168</a> <span class="kw">let </span><span class="kw-2">mut </span>any_changed = <span class="bool-val">false</span>; |
| <a href=#169 id=169 data-nosnippet>169</a> obligations.extend(<span class="self">self</span>.obligations.drain_pending(|<span class="kw">_</span>| <span class="bool-val">true</span>)); |
| <a href=#170 id=170 data-nosnippet>170</a> <span class="kw">for </span>(<span class="kw-2">mut </span>obligation, stalled_on) <span class="kw">in </span>obligations.drain(..) { |
| <a href=#171 id=171 data-nosnippet>171</a> <span class="kw">if </span>obligation.recursion_depth >= infcx.interner.recursion_limit() { |
| <a href=#172 id=172 data-nosnippet>172</a> <span class="self">self</span>.obligations.on_fulfillment_overflow(infcx); |
| <a href=#173 id=173 data-nosnippet>173</a> <span class="comment">// Only return true errors that we have accumulated while processing. |
| <a href=#174 id=174 data-nosnippet>174</a> </span><span class="kw">return </span>errors; |
| <a href=#175 id=175 data-nosnippet>175</a> } |
| <a href=#176 id=176 data-nosnippet>176</a> |
| <a href=#177 id=177 data-nosnippet>177</a> <span class="kw">let </span>goal = obligation.as_goal(); |
| <a href=#178 id=178 data-nosnippet>178</a> <span class="kw">let </span>delegate = <<span class="kw-2">&</span>SolverContext<<span class="lifetime">'db</span>>>::from(infcx); |
| <a href=#179 id=179 data-nosnippet>179</a> <span class="kw">if let </span><span class="prelude-val">Some</span>(certainty) = delegate.compute_goal_fast_path(goal, Span::dummy()) { |
| <a href=#180 id=180 data-nosnippet>180</a> <span class="kw">match </span>certainty { |
| <a href=#181 id=181 data-nosnippet>181</a> Certainty::Yes => {} |
| <a href=#182 id=182 data-nosnippet>182</a> Certainty::Maybe { .. } => { |
| <a href=#183 id=183 data-nosnippet>183</a> <span class="self">self</span>.obligations.register(obligation, <span class="prelude-val">None</span>); |
| <a href=#184 id=184 data-nosnippet>184</a> } |
| <a href=#185 id=185 data-nosnippet>185</a> } |
| <a href=#186 id=186 data-nosnippet>186</a> <span class="kw">continue</span>; |
| <a href=#187 id=187 data-nosnippet>187</a> } |
| <a href=#188 id=188 data-nosnippet>188</a> |
| <a href=#189 id=189 data-nosnippet>189</a> <span class="kw">let </span>result = delegate.evaluate_root_goal(goal, Span::dummy(), stalled_on); |
| <a href=#190 id=190 data-nosnippet>190</a> <span class="kw">let </span>GoalEvaluation { goal: <span class="kw">_</span>, certainty, has_changed, stalled_on } = <span class="kw">match </span>result { |
| <a href=#191 id=191 data-nosnippet>191</a> <span class="prelude-val">Ok</span>(result) => result, |
| <a href=#192 id=192 data-nosnippet>192</a> <span class="prelude-val">Err</span>(NoSolution) => { |
| <a href=#193 id=193 data-nosnippet>193</a> errors.push(NextSolverError::TrueError(obligation)); |
| <a href=#194 id=194 data-nosnippet>194</a> <span class="kw">continue</span>; |
| <a href=#195 id=195 data-nosnippet>195</a> } |
| <a href=#196 id=196 data-nosnippet>196</a> }; |
| <a href=#197 id=197 data-nosnippet>197</a> |
| <a href=#198 id=198 data-nosnippet>198</a> <span class="kw">if </span>has_changed == HasChanged::Yes { |
| <a href=#199 id=199 data-nosnippet>199</a> <span class="comment">// We increment the recursion depth here to track the number of times |
| <a href=#200 id=200 data-nosnippet>200</a> // this goal has resulted in inference progress. This doesn't precisely |
| <a href=#201 id=201 data-nosnippet>201</a> // model the way that we track recursion depth in the old solver due |
| <a href=#202 id=202 data-nosnippet>202</a> // to the fact that we only process root obligations, but it is a good |
| <a href=#203 id=203 data-nosnippet>203</a> // approximation and should only result in fulfillment overflow in |
| <a href=#204 id=204 data-nosnippet>204</a> // pathological cases. |
| <a href=#205 id=205 data-nosnippet>205</a> </span>obligation.recursion_depth += <span class="number">1</span>; |
| <a href=#206 id=206 data-nosnippet>206</a> any_changed = <span class="bool-val">true</span>; |
| <a href=#207 id=207 data-nosnippet>207</a> } |
| <a href=#208 id=208 data-nosnippet>208</a> |
| <a href=#209 id=209 data-nosnippet>209</a> <span class="kw">match </span>certainty { |
| <a href=#210 id=210 data-nosnippet>210</a> Certainty::Yes => {} |
| <a href=#211 id=211 data-nosnippet>211</a> Certainty::Maybe { .. } => <span class="self">self</span>.obligations.register(obligation, stalled_on), |
| <a href=#212 id=212 data-nosnippet>212</a> } |
| <a href=#213 id=213 data-nosnippet>213</a> } |
| <a href=#214 id=214 data-nosnippet>214</a> |
| <a href=#215 id=215 data-nosnippet>215</a> <span class="kw">if </span>!any_changed { |
| <a href=#216 id=216 data-nosnippet>216</a> <span class="kw">break</span>; |
| <a href=#217 id=217 data-nosnippet>217</a> } |
| <a href=#218 id=218 data-nosnippet>218</a> } |
| <a href=#219 id=219 data-nosnippet>219</a> |
| <a href=#220 id=220 data-nosnippet>220</a> errors |
| <a href=#221 id=221 data-nosnippet>221</a> } |
| <a href=#222 id=222 data-nosnippet>222</a> |
| <a href=#223 id=223 data-nosnippet>223</a> <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>evaluate_obligations_error_on_ambiguity( |
| <a href=#224 id=224 data-nosnippet>224</a> <span class="kw-2">&mut </span><span class="self">self</span>, |
| <a href=#225 id=225 data-nosnippet>225</a> infcx: <span class="kw-2">&</span>InferCtxt<<span class="lifetime">'db</span>>, |
| <a href=#226 id=226 data-nosnippet>226</a> ) -> Vec<NextSolverError<<span class="lifetime">'db</span>>> { |
| <a href=#227 id=227 data-nosnippet>227</a> <span class="kw">let </span>errors = <span class="self">self</span>.try_evaluate_obligations(infcx); |
| <a href=#228 id=228 data-nosnippet>228</a> <span class="kw">if </span>!errors.is_empty() { |
| <a href=#229 id=229 data-nosnippet>229</a> <span class="kw">return </span>errors; |
| <a href=#230 id=230 data-nosnippet>230</a> } |
| <a href=#231 id=231 data-nosnippet>231</a> |
| <a href=#232 id=232 data-nosnippet>232</a> <span class="self">self</span>.collect_remaining_errors(infcx) |
| <a href=#233 id=233 data-nosnippet>233</a> } |
| <a href=#234 id=234 data-nosnippet>234</a> |
| <a href=#235 id=235 data-nosnippet>235</a> <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>pending_obligations(<span class="kw-2">&</span><span class="self">self</span>) -> PredicateObligations<<span class="lifetime">'db</span>> { |
| <a href=#236 id=236 data-nosnippet>236</a> <span class="self">self</span>.obligations.clone_pending() |
| <a href=#237 id=237 data-nosnippet>237</a> } |
| <a href=#238 id=238 data-nosnippet>238</a> |
| <a href=#239 id=239 data-nosnippet>239</a> <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>drain_stalled_obligations_for_coroutines( |
| <a href=#240 id=240 data-nosnippet>240</a> <span class="kw-2">&mut </span><span class="self">self</span>, |
| <a href=#241 id=241 data-nosnippet>241</a> infcx: <span class="kw-2">&</span>InferCtxt<<span class="lifetime">'db</span>>, |
| <a href=#242 id=242 data-nosnippet>242</a> ) -> PredicateObligations<<span class="lifetime">'db</span>> { |
| <a href=#243 id=243 data-nosnippet>243</a> <span class="kw">let </span>stalled_coroutines = <span class="kw">match </span>infcx.typing_mode() { |
| <a href=#244 id=244 data-nosnippet>244</a> TypingMode::Analysis { defining_opaque_types_and_generators } => { |
| <a href=#245 id=245 data-nosnippet>245</a> defining_opaque_types_and_generators |
| <a href=#246 id=246 data-nosnippet>246</a> } |
| <a href=#247 id=247 data-nosnippet>247</a> TypingMode::Coherence |
| <a href=#248 id=248 data-nosnippet>248</a> | TypingMode::Borrowck { defining_opaque_types: <span class="kw">_ </span>} |
| <a href=#249 id=249 data-nosnippet>249</a> | TypingMode::PostBorrowckAnalysis { defined_opaque_types: <span class="kw">_ </span>} |
| <a href=#250 id=250 data-nosnippet>250</a> | TypingMode::PostAnalysis => <span class="kw">return </span>Default::default(), |
| <a href=#251 id=251 data-nosnippet>251</a> }; |
| <a href=#252 id=252 data-nosnippet>252</a> <span class="kw">let </span>stalled_coroutines = stalled_coroutines.inner(); |
| <a href=#253 id=253 data-nosnippet>253</a> |
| <a href=#254 id=254 data-nosnippet>254</a> <span class="kw">if </span>stalled_coroutines.is_empty() { |
| <a href=#255 id=255 data-nosnippet>255</a> <span class="kw">return </span>Default::default(); |
| <a href=#256 id=256 data-nosnippet>256</a> } |
| <a href=#257 id=257 data-nosnippet>257</a> |
| <a href=#258 id=258 data-nosnippet>258</a> <span class="self">self</span>.obligations |
| <a href=#259 id=259 data-nosnippet>259</a> .drain_pending(|obl| { |
| <a href=#260 id=260 data-nosnippet>260</a> infcx.probe(|<span class="kw">_</span>| { |
| <a href=#261 id=261 data-nosnippet>261</a> infcx |
| <a href=#262 id=262 data-nosnippet>262</a> .visit_proof_tree( |
| <a href=#263 id=263 data-nosnippet>263</a> obl.as_goal(), |
| <a href=#264 id=264 data-nosnippet>264</a> <span class="kw-2">&mut </span>StalledOnCoroutines { |
| <a href=#265 id=265 data-nosnippet>265</a> stalled_coroutines, |
| <a href=#266 id=266 data-nosnippet>266</a> cache: Default::default(), |
| <a href=#267 id=267 data-nosnippet>267</a> }, |
| <a href=#268 id=268 data-nosnippet>268</a> ) |
| <a href=#269 id=269 data-nosnippet>269</a> .is_break() |
| <a href=#270 id=270 data-nosnippet>270</a> }) |
| <a href=#271 id=271 data-nosnippet>271</a> }) |
| <a href=#272 id=272 data-nosnippet>272</a> .map(|(o, <span class="kw">_</span>)| o) |
| <a href=#273 id=273 data-nosnippet>273</a> .collect() |
| <a href=#274 id=274 data-nosnippet>274</a> } |
| <a href=#275 id=275 data-nosnippet>275</a>} |
| <a href=#276 id=276 data-nosnippet>276</a> |
| <a href=#277 id=277 data-nosnippet>277</a><span class="doccomment">/// Detect if a goal is stalled on a coroutine that is owned by the current typeck root. |
| <a href=#278 id=278 data-nosnippet>278</a>/// |
| <a href=#279 id=279 data-nosnippet>279</a>/// This function can (erroneously) fail to detect a predicate, i.e. it doesn't need to |
| <a href=#280 id=280 data-nosnippet>280</a>/// be complete. However, this will lead to ambiguity errors, so we want to make it |
| <a href=#281 id=281 data-nosnippet>281</a>/// accurate. |
| <a href=#282 id=282 data-nosnippet>282</a>/// |
| <a href=#283 id=283 data-nosnippet>283</a>/// This function can be also return false positives, which will lead to poor diagnostics |
| <a href=#284 id=284 data-nosnippet>284</a>/// so we want to keep this visitor *precise* too. |
| <a href=#285 id=285 data-nosnippet>285</a></span><span class="kw">pub struct </span>StalledOnCoroutines<<span class="lifetime">'a</span>, <span class="lifetime">'db</span>> { |
| <a href=#286 id=286 data-nosnippet>286</a> <span class="kw">pub </span>stalled_coroutines: <span class="kw-2">&</span><span class="lifetime">'a </span>[SolverDefId], |
| <a href=#287 id=287 data-nosnippet>287</a> <span class="kw">pub </span>cache: FxHashSet<Ty<<span class="lifetime">'db</span>>>, |
| <a href=#288 id=288 data-nosnippet>288</a>} |
| <a href=#289 id=289 data-nosnippet>289</a> |
| <a href=#290 id=290 data-nosnippet>290</a><span class="kw">impl</span><<span class="lifetime">'db</span>> ProofTreeVisitor<<span class="lifetime">'db</span>> <span class="kw">for </span>StalledOnCoroutines<<span class="lifetime">'_</span>, <span class="lifetime">'db</span>> { |
| <a href=#291 id=291 data-nosnippet>291</a> <span class="kw">type </span><span class="prelude-ty">Result</span> = ControlFlow<()>; |
| <a href=#292 id=292 data-nosnippet>292</a> |
| <a href=#293 id=293 data-nosnippet>293</a> <span class="kw">fn </span>visit_goal(<span class="kw-2">&mut </span><span class="self">self</span>, inspect_goal: <span class="kw-2">&</span><span class="kw">super</span>::inspect::InspectGoal<<span class="lifetime">'_</span>, <span class="lifetime">'db</span>>) -> <span class="self">Self</span>::Result { |
| <a href=#294 id=294 data-nosnippet>294</a> inspect_goal.goal().predicate.visit_with(<span class="self">self</span>)<span class="question-mark">?</span>; |
| <a href=#295 id=295 data-nosnippet>295</a> |
| <a href=#296 id=296 data-nosnippet>296</a> <span class="kw">if let </span><span class="prelude-val">Some</span>(candidate) = inspect_goal.unique_applicable_candidate() { |
| <a href=#297 id=297 data-nosnippet>297</a> candidate.visit_nested_no_probe(<span class="self">self</span>) |
| <a href=#298 id=298 data-nosnippet>298</a> } <span class="kw">else </span>{ |
| <a href=#299 id=299 data-nosnippet>299</a> ControlFlow::Continue(()) |
| <a href=#300 id=300 data-nosnippet>300</a> } |
| <a href=#301 id=301 data-nosnippet>301</a> } |
| <a href=#302 id=302 data-nosnippet>302</a>} |
| <a href=#303 id=303 data-nosnippet>303</a> |
| <a href=#304 id=304 data-nosnippet>304</a><span class="kw">impl</span><<span class="lifetime">'db</span>> TypeVisitor<DbInterner<<span class="lifetime">'db</span>>> <span class="kw">for </span>StalledOnCoroutines<<span class="lifetime">'_</span>, <span class="lifetime">'db</span>> { |
| <a href=#305 id=305 data-nosnippet>305</a> <span class="kw">type </span><span class="prelude-ty">Result</span> = ControlFlow<()>; |
| <a href=#306 id=306 data-nosnippet>306</a> |
| <a href=#307 id=307 data-nosnippet>307</a> <span class="kw">fn </span>visit_ty(<span class="kw-2">&mut </span><span class="self">self</span>, ty: Ty<<span class="lifetime">'db</span>>) -> <span class="self">Self</span>::Result { |
| <a href=#308 id=308 data-nosnippet>308</a> <span class="kw">if </span>!<span class="self">self</span>.cache.insert(ty) { |
| <a href=#309 id=309 data-nosnippet>309</a> <span class="kw">return </span>ControlFlow::Continue(()); |
| <a href=#310 id=310 data-nosnippet>310</a> } |
| <a href=#311 id=311 data-nosnippet>311</a> |
| <a href=#312 id=312 data-nosnippet>312</a> <span class="kw">if let </span>TyKind::Coroutine(def_id, <span class="kw">_</span>) = ty.kind() |
| <a href=#313 id=313 data-nosnippet>313</a> && <span class="self">self</span>.stalled_coroutines.contains(<span class="kw-2">&</span>def_id.into()) |
| <a href=#314 id=314 data-nosnippet>314</a> { |
| <a href=#315 id=315 data-nosnippet>315</a> ControlFlow::Break(()) |
| <a href=#316 id=316 data-nosnippet>316</a> } <span class="kw">else if </span>ty.has_coroutines() { |
| <a href=#317 id=317 data-nosnippet>317</a> ty.super_visit_with(<span class="self">self</span>) |
| <a href=#318 id=318 data-nosnippet>318</a> } <span class="kw">else </span>{ |
| <a href=#319 id=319 data-nosnippet>319</a> ControlFlow::Continue(()) |
| <a href=#320 id=320 data-nosnippet>320</a> } |
| <a href=#321 id=321 data-nosnippet>321</a> } |
| <a href=#322 id=322 data-nosnippet>322</a>} |
| <a href=#323 id=323 data-nosnippet>323</a> |
| <a href=#324 id=324 data-nosnippet>324</a><span class="attr">#[derive(Debug)] |
| <a href=#325 id=325 data-nosnippet>325</a></span><span class="kw">pub enum </span>NextSolverError<<span class="lifetime">'db</span>> { |
| <a href=#326 id=326 data-nosnippet>326</a> TrueError(PredicateObligation<<span class="lifetime">'db</span>>), |
| <a href=#327 id=327 data-nosnippet>327</a> Ambiguity(PredicateObligation<<span class="lifetime">'db</span>>), |
| <a href=#328 id=328 data-nosnippet>328</a> Overflow(PredicateObligation<<span class="lifetime">'db</span>>), |
| <a href=#329 id=329 data-nosnippet>329</a>} |
| <a href=#330 id=330 data-nosnippet>330</a> |
| <a href=#331 id=331 data-nosnippet>331</a><span class="kw">impl </span>NextSolverError<<span class="lifetime">'_</span>> { |
| <a href=#332 id=332 data-nosnippet>332</a> <span class="attr">#[inline] |
| <a href=#333 id=333 data-nosnippet>333</a> </span><span class="kw">pub fn </span>is_true_error(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <a href=#334 id=334 data-nosnippet>334</a> <span class="macro">matches!</span>(<span class="self">self</span>, NextSolverError::TrueError(<span class="kw">_</span>)) |
| <a href=#335 id=335 data-nosnippet>335</a> } |
| <a href=#336 id=336 data-nosnippet>336</a>}</code></pre></div></section></main></body></html> |
