[clang-cl] Alias /Zc:alignedNew[-] to -f[no-]aligned-allocation

Implements PR40180.

clang-cl has one minor behavior difference with cl with this change.
Clang allows the user to enable the C++17 feature of aligned allocation
without enabling all of C++17, but MSVC will not call the aligned
allocation overloads unless -std:c++17 is passed. While our behavior is
technically incompatible, it would require making driver mode specific
changes to match MSVC precisely, and clang's behavior is useful because
it allows people to experiment with new C++17 features individually.
Therefore, I plan to leave it as is.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@351249 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/clang/Driver/CLCompatOptions.td b/include/clang/Driver/CLCompatOptions.td
index b09ea41049d14b0fc2e8b3364d140f6754d73cbd..3e0dc2db7d07ef7d4f051beee5503f46843aaa33 100644 (file)
--- a/include/clang/Driver/CLCompatOptions.td
+++ b/include/clang/Driver/CLCompatOptions.td
@@ -207,6 +207,12 @@ def _SLASH_Zc_sizedDealloc : CLFlag<"Zc:sizedDealloc">,
 def _SLASH_Zc_sizedDealloc_ : CLFlag<"Zc:sizedDealloc-">,
   HelpText<"Disable C++14 sized global deallocation functions">,
   Alias<fno_sized_deallocation>;
+def _SLASH_Zc_alignedNew : CLFlag<"Zc:alignedNew">,
+  HelpText<"Enable C++17 aligned allocation functions">,
+  Alias<faligned_allocation>;
+def _SLASH_Zc_alignedNew_ : CLFlag<"Zc:alignedNew-">,
+  HelpText<"Disable C++17 aligned allocation functions">,
+  Alias<fno_aligned_allocation>;
 def _SLASH_Zc_strictStrings : CLFlag<"Zc:strictStrings">,
   HelpText<"Treat string literals as const">, Alias<W_Joined>,
   AliasArgs<["error=c++11-compat-deprecated-writable-strings"]>;

diff --git a/test/Driver/cl-zc.cpp b/test/Driver/cl-zc.cpp
index 4414eb6ebba264bd3697319c1b852a5d47e9b8fc..cf7734875e1f1f7dd1b95e06a374f4393f931c9a 100644 (file)
--- a/test/Driver/cl-zc.cpp
+++ b/test/Driver/cl-zc.cpp
@@ -18,6 +18,12 @@
 // RUN: %clang_cl /c -### /Zc:sizedDealloc- -- %s 2>&1 | FileCheck -check-prefix=SIZED-DEALLOC-OFF %s
 // SIZED-DEALLOC-OFF-NOT: "-fsized-deallocation"
 
+// RUN: %clang_cl /c /std:c++17 -### /Zc:alignedNew -- %s 2>&1 | FileCheck -check-prefix=ALIGNED-NEW-ON %s
+// ALIGNED-NEW-ON: "-faligned-allocation"
+
+// RUN: %clang_cl /c /std:c++17 -### /Zc:alignedNew- -- %s 2>&1 | FileCheck -check-prefix=ALIGNED-NEW-OFF %s
+// ALIGNED-NEW-OFF-NOT: "-faligned-allocation"
+
 // RUN: %clang_cl /c -### -- %s 2>&1 | FileCheck -check-prefix=STRICTSTRINGS-DEFAULT %s
 // STRICTSTRINGS-DEFAULT-NOT: -Werror=c++11-compat-deprecated-writable-strings
 // RUN: %clang_cl /c -### /Zc:strictStrings -- %s 2>&1 | FileCheck -check-prefix=STRICTSTRINGS-ON %s