diff options
Diffstat (limited to 'compiler/semexprs.nim')
| -rw-r--r-- | compiler/semexprs.nim | 27 |
1 files changed, 18 insertions, 9 deletions
diff --git a/compiler/semexprs.nim b/compiler/semexprs.nim index 6070464c9..c4af23811 100644 --- a/compiler/semexprs.nim +++ b/compiler/semexprs.nim @@ -736,7 +736,7 @@ proc hasUnresolvedArgs(c: PContext, n: PNode): bool = if hasUnresolvedArgs(c, n[i]): return true return false -proc newHiddenAddrTaken(c: PContext, n: PNode): PNode = +proc newHiddenAddrTaken(c: PContext, n: PNode, isOutParam: bool): PNode = if n.kind == nkHiddenDeref and not (c.config.backend == backendCpp or sfCompileToCpp in c.module.flags): checkSonsLen(n, 1, c.config) @@ -745,13 +745,17 @@ proc newHiddenAddrTaken(c: PContext, n: PNode): PNode = result = newNodeIT(nkHiddenAddr, n.info, makeVarType(c, n.typ)) result.add n let aa = isAssignable(c, n) + let sym = getRoot(n) if aa notin {arLValue, arLocalLValue}: if aa == arDiscriminant and c.inUncheckedAssignSection > 0: discard "allow access within a cast(unsafeAssign) section" + elif strictDefs in c.features and aa == arAddressableConst and + sym != nil and sym.kind == skLet and isOutParam: + discard "allow let varaibles to be passed to out parameters" else: localError(c.config, n.info, errVarForOutParamNeededX % renderNotLValue(n)) -proc analyseIfAddressTaken(c: PContext, n: PNode): PNode = +proc analyseIfAddressTaken(c: PContext, n: PNode, isOutParam: bool): PNode = result = n case n.kind of nkSym: @@ -759,7 +763,7 @@ proc analyseIfAddressTaken(c: PContext, n: PNode): PNode = if n.sym.typ != nil and skipTypes(n.sym.typ, abstractInst-{tyTypeDesc}).kind notin {tyVar, tyLent}: incl(n.sym.flags, sfAddrTaken) - result = newHiddenAddrTaken(c, n) + result = newHiddenAddrTaken(c, n, isOutParam) of nkDotExpr: checkSonsLen(n, 2, c.config) if n[1].kind != nkSym: @@ -767,14 +771,14 @@ proc analyseIfAddressTaken(c: PContext, n: PNode): PNode = return if skipTypes(n[1].sym.typ, abstractInst-{tyTypeDesc}).kind notin {tyVar, tyLent}: incl(n[1].sym.flags, sfAddrTaken) - result = newHiddenAddrTaken(c, n) + result = newHiddenAddrTaken(c, n, isOutParam) of nkBracketExpr: checkMinSonsLen(n, 1, c.config) if skipTypes(n[0].typ, abstractInst-{tyTypeDesc}).kind notin {tyVar, tyLent}: if n[0].kind == nkSym: incl(n[0].sym.flags, sfAddrTaken) - result = newHiddenAddrTaken(c, n) + result = newHiddenAddrTaken(c, n, isOutParam) else: - result = newHiddenAddrTaken(c, n) + result = newHiddenAddrTaken(c, n, isOutParam) proc analyseIfAddressTakenInCall(c: PContext, n: PNode) = checkMinSonsLen(n, 1, c.config) @@ -820,7 +824,7 @@ proc analyseIfAddressTakenInCall(c: PContext, n: PNode) = if i < t.len and skipTypes(t[i], abstractInst-{tyTypeDesc}).kind in {tyVar}: if n[i].kind != nkHiddenAddr: - n[i] = analyseIfAddressTaken(c, n[i]) + n[i] = analyseIfAddressTaken(c, n[i], isOutParam(skipTypes(t[i], abstractInst-{tyTypeDesc}))) include semmagic @@ -1812,11 +1816,16 @@ proc semAsgn(c: PContext, n: PNode; mode=asgnNormal): PNode = # a = b # both are vars, means: a[] = b[] # a = b # b no 'var T' means: a = addr(b) var le = a.typ + let assignable = isAssignable(c, a) + let root = getRoot(a) + let useStrictDefLet = root != nil and root.kind == skLet and + assignable == arAddressableConst and + strictDefs in c.features and isLocalSym(root) if le == nil: localError(c.config, a.info, "expression has no type") elif (skipTypes(le, {tyGenericInst, tyAlias, tySink}).kind notin {tyVar} and - isAssignable(c, a) in {arNone, arLentValue, arAddressableConst}) or ( - skipTypes(le, abstractVar).kind in {tyOpenArray, tyVarargs} and views notin c.features): + assignable in {arNone, arLentValue, arAddressableConst} and not useStrictDefLet + ) or (skipTypes(le, abstractVar).kind in {tyOpenArray, tyVarargs} and views notin c.features): # Direct assignment to a discriminant is allowed! localError(c.config, a.info, errXCannotBeAssignedTo % renderTree(a, {renderNoComments})) |