From 649c6c50fd3dd13577071b26fec4495f7538d923 Mon Sep 17 00:00:00 2001 From: Hans Wennborg Date: Thu, 6 Jun 2013 09:16:36 +0000 Subject: [PATCH] Disallow reinterpret_cast from pointer to bool on Windows This became allowed by accident in r131201, but triggers an assert. That patch added an exception to allow conversion from pointers to narrow integral types for MSVC compatibility. However, a pointer can already be converted to bool in a civilized manner; allowing conversion via reinterpret_cast is a bad idea. Fixes PR16222. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@183394 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Sema/SemaCast.cpp | 6 ++++-- test/Sema/MicrosoftExtensions.c | 3 +++ test/SemaCXX/MicrosoftExtensions.cpp | 8 +++++++- 3 files changed, 14 insertions(+), 3 deletions(-) diff --git a/lib/Sema/SemaCast.cpp b/lib/Sema/SemaCast.cpp index 3f0a1a36e4..b4e7113319 100644 --- a/lib/Sema/SemaCast.cpp +++ b/lib/Sema/SemaCast.cpp @@ -1813,10 +1813,12 @@ static TryCastResult TryReinterpretCast(Sema &Self, ExprResult &SrcExpr, assert(srcIsPtr && "One type must be a pointer"); // C++ 5.2.10p4: A pointer can be explicitly converted to any integral // type large enough to hold it; except in Microsoft mode, where the - // integral type size doesn't matter. + // integral type size doesn't matter (except we don't allow bool). + bool MicrosoftException = Self.getLangOpts().MicrosoftExt && + !DestType->isBooleanType(); if ((Self.Context.getTypeSize(SrcType) > Self.Context.getTypeSize(DestType)) && - !Self.getLangOpts().MicrosoftExt) { + !MicrosoftException) { msg = diag::err_bad_reinterpret_cast_small_int; return TC_Failed; } diff --git a/test/Sema/MicrosoftExtensions.c b/test/Sema/MicrosoftExtensions.c index a66d9a9eb0..5215e72b1b 100644 --- a/test/Sema/MicrosoftExtensions.c +++ b/test/Sema/MicrosoftExtensions.c @@ -76,6 +76,9 @@ void pointer_to_integral_type_conv(char* ptr) { short sh = (short)ptr; ch = (char)ptr; sh = (short)ptr; + + // This is valid ISO C. + _Bool b = (_Bool)ptr; } diff --git a/test/SemaCXX/MicrosoftExtensions.cpp b/test/SemaCXX/MicrosoftExtensions.cpp index 93a6d302ef..c0e7a5ad4c 100644 --- a/test/SemaCXX/MicrosoftExtensions.cpp +++ b/test/SemaCXX/MicrosoftExtensions.cpp @@ -167,8 +167,14 @@ void pointer_to_integral_type_conv(char* ptr) { short sh = (short)ptr; ch = (char)ptr; sh = (short)ptr; -} + // These are valid C++. + bool b = (bool)ptr; + b = static_cast(ptr); + + // This is bad. + b = reinterpret_cast(ptr); // expected-error {{cast from pointer to smaller type 'bool' loses information}} +} namespace friend_as_a_forward_decl { -- 2.40.0