diff options
Diffstat (limited to 'compiler/semcall.nim')
| -rw-r--r-- | compiler/semcall.nim | 140 |
1 files changed, 95 insertions, 45 deletions
diff --git a/compiler/semcall.nim b/compiler/semcall.nim index a51b9afe3..df99d6c24 100644 --- a/compiler/semcall.nim +++ b/compiler/semcall.nim @@ -59,7 +59,8 @@ proc pickBestCandidate(c: PContext, headSymbol: PNode, filter: TSymKinds, best, alt: var TCandidate, errors: var CandidateErrors, - diagnosticsFlag = false) = + diagnosticsFlag: bool, + errorsEnabled: bool) = var o: TOverloadIter var sym = initOverloadIter(o, c, headSymbol) var scope = o.lastOverloadScope @@ -68,6 +69,7 @@ proc pickBestCandidate(c: PContext, headSymbol: PNode, # This can occur in cases like 'init(a, 1, (var b = new(Type2); b))' let counterInitial = c.currentScope.symbols.counter var syms: seq[tuple[s: PSym, scope: int]] + var noSyms = true var nextSymIndex = 0 while sym != nil: if sym.kind in filter: @@ -102,17 +104,19 @@ proc pickBestCandidate(c: PContext, headSymbol: PNode, var cmp = cmpCandidates(best, z) if cmp < 0: best = z # x is better than the best so far elif cmp == 0: alt = z # x is as good as the best so far - elif errors != nil or z.diagnostics != nil: + elif errorsEnabled or z.diagnosticsEnabled: errors.safeAdd(CandidateError( sym: sym, unmatchedVarParam: int z.mutabilityProblem, + firstMismatch: z.firstMismatch, diagnostics: z.diagnostics)) else: # Symbol table has been modified. Restart and pre-calculate all syms # before any further candidate init and compare. SLOW, but rare case. syms = initCandidateSymbols(c, headSymbol, initialBinding, filter, best, alt, o, diagnosticsFlag) - if syms == nil: + noSyms = false + if noSyms: sym = nextOverloadIter(o, c, headSymbol) scope = o.lastOverloadScope elif nextSymIndex < syms.len: @@ -123,6 +127,20 @@ proc pickBestCandidate(c: PContext, headSymbol: PNode, else: break +proc effectProblem(f, a: PType; result: var string) = + if f.kind == tyProc and a.kind == tyProc: + if tfThread in f.flags and tfThread notin a.flags: + result.add "\n This expression is not GC-safe. Annotate the " & + "proc with {.gcsafe.} to get extended error information." + elif tfNoSideEffect in f.flags and tfNoSideEffect notin a.flags: + result.add "\n This expression can have side effects. Annotate the " & + "proc with {.noSideEffect.} to get extended error information." + +proc renderNotLValue(n: PNode): string = + result = $n + if n.kind in {nkHiddenStdConv, nkHiddenSubConv, nkHiddenCallConv} and n.len == 2: + result = typeToString(n.typ.skipTypes(abstractVar)) & "(" & result & ")" + proc presentFailedCandidates(c: PContext, n: PNode, errors: CandidateErrors): (TPreferedDesc, string) = var prefer = preferName @@ -154,32 +172,61 @@ proc presentFailedCandidates(c: PContext, n: PNode, errors: CandidateErrors): else: add(candidates, err.sym.getProcHeader(prefer)) add(candidates, "\n") + if err.firstMismatch != 0 and n.len > 1: + let cond = n.len > 2 + if cond: + candidates.add(" first type mismatch at position: " & $err.firstMismatch & + "\n required type: ") + var wanted, got: PType = nil + if err.firstMismatch < err.sym.typ.len: + wanted = err.sym.typ.sons[err.firstMismatch] + if cond: candidates.add typeToString(wanted) + else: + if cond: candidates.add "none" + if err.firstMismatch < n.len: + if cond: + candidates.add "\n but expression '" + candidates.add renderTree(n[err.firstMismatch]) + candidates.add "' is of type: " + got = n[err.firstMismatch].typ + if cond: candidates.add typeToString(got) + if wanted != nil and got != nil: + effectProblem(wanted, got, candidates) + if cond: candidates.add "\n" if err.unmatchedVarParam != 0 and err.unmatchedVarParam < n.len: - add(candidates, "for a 'var' type a variable needs to be passed, but '" & - renderTree(n[err.unmatchedVarParam]) & "' is immutable\n") + candidates.add(" for a 'var' type a variable needs to be passed, but '" & + renderNotLValue(n[err.unmatchedVarParam]) & + "' is immutable\n") for diag in err.diagnostics: - add(candidates, diag & "\n") + candidates.add(diag & "\n") result = (prefer, candidates) +const + errTypeMismatch = "type mismatch: got <" + errButExpected = "but expected one of: " + errUndeclaredField = "undeclared field: '$1'" + errUndeclaredRoutine = "attempting to call undeclared routine: '$1'" + errAmbiguousCallXYZ = "ambiguous call; both $1 and $2 match for: $3" + proc notFoundError*(c: PContext, n: PNode, errors: CandidateErrors) = # Gives a detailed error message; this is separated from semOverloadedCall, # as semOverlodedCall is already pretty slow (and we need this information # only in case of an error). if errorOutputs == {}: # fail fast: - globalError(n.info, errTypeMismatch, "") - if errors.isNil or errors.len == 0: - localError(n.info, errExprXCannotBeCalled, n[0].renderTree) + globalError(c.config, n.info, "type mismatch") + if errors.len == 0: + localError(c.config, n.info, "expression '$1' cannot be called" % n[0].renderTree) return let (prefer, candidates) = presentFailedCandidates(c, n, errors) - var result = msgKindToString(errTypeMismatch) + var result = errTypeMismatch add(result, describeArgs(c, n, 1, prefer)) - add(result, ')') + add(result, '>') if candidates != "": - add(result, "\n" & msgKindToString(errButExpected) & "\n" & candidates) - localError(n.info, errGenerated, result & "\nexpression: " & $n) + add(result, "\n" & errButExpected & "\n" & candidates) + localError(c.config, n.info, result & "\nexpression: " & $n) proc bracketNotFoundError(c: PContext; n: PNode) = var errors: CandidateErrors = @[] @@ -189,22 +236,25 @@ proc bracketNotFoundError(c: PContext; n: PNode) = while symx != nil: if symx.kind in routineKinds: errors.add(CandidateError(sym: symx, - unmatchedVarParam: 0, - diagnostics: nil)) + unmatchedVarParam: 0, firstMismatch: 0, + diagnostics: nil, + enabled: false)) symx = nextOverloadIter(o, c, headSymbol) if errors.len == 0: - localError(n.info, "could not resolve: " & $n) + localError(c.config, n.info, "could not resolve: " & $n) else: notFoundError(c, n, errors) proc resolveOverloads(c: PContext, n, orig: PNode, filter: TSymKinds, flags: TExprFlags, - errors: var CandidateErrors): TCandidate = + errors: var CandidateErrors, + errorsEnabled: bool): TCandidate = var initialBinding: PNode var alt: TCandidate var f = n.sons[0] if f.kind == nkBracketExpr: # fill in the bindings: + semOpAux(c, f) initialBinding = f f = f.sons[0] else: @@ -212,7 +262,8 @@ proc resolveOverloads(c: PContext, n, orig: PNode, template pickBest(headSymbol) = pickBestCandidate(c, headSymbol, n, orig, initialBinding, - filter, result, alt, errors, efExplain in flags) + filter, result, alt, errors, efExplain in flags, + errorsEnabled) pickBest(f) let overloadsState = result.state @@ -234,7 +285,7 @@ proc resolveOverloads(c: PContext, n, orig: PNode, else: return if nfDotField in n.flags: - internalAssert f.kind == nkIdent and n.sonsLen >= 2 + internalAssert c.config, f.kind == nkIdent and n.len >= 2 # leave the op head symbol empty, # we are going to try multiple variants @@ -263,13 +314,13 @@ proc resolveOverloads(c: PContext, n, orig: PNode, if overloadsState == csEmpty and result.state == csEmpty: if nfDotField in n.flags and nfExplicitCall notin n.flags: - localError(n.info, errUndeclaredField, considerQuotedIdent(f).s) + localError(c.config, n.info, errUndeclaredField % considerQuotedIdent(c.config, f, n).s) else: - localError(n.info, errUndeclaredRoutine, considerQuotedIdent(f).s) + localError(c.config, n.info, errUndeclaredRoutine % considerQuotedIdent(c.config, f, n).s) return elif result.state != csMatch: if nfExprCall in n.flags: - localError(n.info, errExprXCannotBeCalled, + localError(c.config, n.info, "expression '$1' cannot be called" % renderTree(n, {renderNoComments})) else: if {nfDotField, nfDotSetter} * n.flags != {}: @@ -279,13 +330,13 @@ proc resolveOverloads(c: PContext, n, orig: PNode, return if alt.state == csMatch and cmpCandidates(result, alt) == 0 and not sameMethodDispatcher(result.calleeSym, alt.calleeSym): - internalAssert result.state == csMatch + internalAssert c.config, result.state == csMatch #writeMatches(result) #writeMatches(alt) if errorOutputs == {}: # quick error message for performance of 'compiles' built-in: - globalError(n.info, errGenerated, "ambiguous call") - elif gErrorCounter == 0: + globalError(c.config, n.info, errGenerated, "ambiguous call") + elif c.config.errorCounter == 0: # don't cascade errors var args = "(" for i in countup(1, sonsLen(n) - 1): @@ -293,7 +344,7 @@ proc resolveOverloads(c: PContext, n, orig: PNode, add(args, typeToString(n.sons[i].typ)) add(args, ")") - localError(n.info, errGenerated, msgKindToString(errAmbiguousCallXYZ) % [ + localError(c.config, n.info, errAmbiguousCallXYZ % [ getProcHeader(result.calleeSym), getProcHeader(alt.calleeSym), args]) @@ -334,7 +385,7 @@ proc inferWithMetatype(c: PContext, formal: PType, result.typ = generateTypeInstance(c, m.bindings, arg.info, formal.skipTypes({tyCompositeTypeClass})) else: - typeMismatch(arg.info, formal, arg.typ) + typeMismatch(c.config, arg.info, formal, arg.typ) # error correction: result = copyTree(arg) result.typ = formal @@ -342,7 +393,7 @@ proc inferWithMetatype(c: PContext, formal: PType, proc semResolvedCall(c: PContext, n: PNode, x: TCandidate): PNode = assert x.state == csMatch var finalCallee = x.calleeSym - markUsed(n.sons[0].info, finalCallee, c.graph.usageSym) + markUsed(c.config, n.sons[0].info, finalCallee, c.graph.usageSym) styleCheckUse(n.sons[0].info, finalCallee) assert finalCallee.ast != nil if x.hasFauxMatch: @@ -368,7 +419,7 @@ proc semResolvedCall(c: PContext, n: PNode, x: TCandidate): PNode = of skType: x.call.add newSymNode(s, n.info) else: - internalAssert false + internalAssert c.config, false result = x.call instGenericConvertersSons(c, result, x) @@ -377,7 +428,7 @@ proc semResolvedCall(c: PContext, n: PNode, x: TCandidate): PNode = proc canDeref(n: PNode): bool {.inline.} = result = n.len >= 2 and (let t = n[1].typ; - t != nil and t.skipTypes({tyGenericInst, tyAlias}).kind in {tyPtr, tyRef}) + t != nil and t.skipTypes({tyGenericInst, tyAlias, tySink}).kind in {tyPtr, tyRef}) proc tryDeref(n: PNode): PNode = result = newNodeI(nkHiddenDeref, n.info) @@ -386,18 +437,17 @@ proc tryDeref(n: PNode): PNode = proc semOverloadedCall(c: PContext, n, nOrig: PNode, filter: TSymKinds, flags: TExprFlags): PNode = - var errors: CandidateErrors = if efExplain in flags: @[] - else: nil - var r = resolveOverloads(c, n, nOrig, filter, flags, errors) + var errors: CandidateErrors = if efExplain in flags: @[] else: nil + var r = resolveOverloads(c, n, nOrig, filter, flags, errors, efExplain in flags) if r.state == csMatch: # this may be triggered, when the explain pragma is used if errors.len > 0: let (_, candidates) = presentFailedCandidates(c, n, errors) - message(n.info, hintUserRaw, + message(c.config, n.info, hintUserRaw, "Non-matching candidates for " & renderTree(n) & "\n" & candidates) result = semResolvedCall(c, n, r) - elif experimentalMode(c) and canDeref(n): + elif implicitDeref in c.features and canDeref(n): # try to deref the first argument and then try overloading resolution again: # # XXX: why is this here? @@ -406,7 +456,7 @@ proc semOverloadedCall(c: PContext, n, nOrig: PNode, # into sigmatch with hidden conversion produced there # n.sons[1] = n.sons[1].tryDeref - var r = resolveOverloads(c, n, nOrig, filter, flags, errors) + var r = resolveOverloads(c, n, nOrig, filter, flags, errors, efExplain in flags) if r.state == csMatch: result = semResolvedCall(c, n, r) else: # get rid of the deref again for a better error message: @@ -426,8 +476,8 @@ proc semOverloadedCall(c: PContext, n, nOrig: PNode, else: notFoundError(c, n, errors) -proc explicitGenericInstError(n: PNode): PNode = - localError(n.info, errCannotInstantiateX, renderTree(n)) +proc explicitGenericInstError(c: PContext; n: PNode): PNode = + localError(c.config, n.info, errCannotInstantiateX % renderTree(n)) result = n proc explicitGenericSym(c: PContext, n: PNode, s: PSym): PNode = @@ -442,7 +492,7 @@ proc explicitGenericSym(c: PContext, n: PNode, s: PSym): PNode = if tm in {isNone, isConvertible}: return nil var newInst = generateInstance(c, s, m.bindings, n.info) newInst.typ.flags.excl tfUnresolved - markUsed(n.info, s, c.graph.usageSym) + markUsed(c.config, n.info, s, c.graph.usageSym) styleCheckUse(n.info, s) result = newSymNode(newInst, n.info) @@ -458,11 +508,11 @@ proc explicitGenericInstantiation(c: PContext, n: PNode, s: PSym): PNode = # number of generic type parameters: if safeLen(s.ast.sons[genericParamsPos]) != n.len-1: let expected = safeLen(s.ast.sons[genericParamsPos]) - localError(n.info, errGenerated, "cannot instantiate: " & renderTree(n) & - "; got " & $(n.len-1) & " type(s) but expected " & $expected) + localError(c.config, n.info, errGenerated, "cannot instantiate: '" & renderTree(n) & + "'; got " & $(n.len-1) & " type(s) but expected " & $expected) return n result = explicitGenericSym(c, n, s) - if result == nil: result = explicitGenericInstError(n) + if result == nil: result = explicitGenericInstError(c, n) elif a.kind in {nkClosedSymChoice, nkOpenSymChoice}: # choose the generic proc with the proper number of type parameters. # XXX I think this could be improved by reusing sigmatch.paramTypesMatch. @@ -480,10 +530,10 @@ proc explicitGenericInstantiation(c: PContext, n: PNode, s: PSym): PNode = # get rid of nkClosedSymChoice if not ambiguous: if result.len == 1 and a.kind == nkClosedSymChoice: result = result[0] - elif result.len == 0: result = explicitGenericInstError(n) - # candidateCount != 1: return explicitGenericInstError(n) + elif result.len == 0: result = explicitGenericInstError(c, n) + # candidateCount != 1: return explicitGenericInstError(c, n) else: - result = explicitGenericInstError(n) + result = explicitGenericInstError(c, n) proc searchForBorrowProc(c: PContext, startScope: PScope, fn: PSym): PSym = # Searchs for the fn in the symbol table. If the parameter lists are suitable |