CodeGenModule: Always output wchar_size, check LLVM assumptions.
Re-commit r303463 now that LLVM is fixed and adjust some lit tests.
llvm::TargetLibraryInfo needs to know the size of wchar_t to work on
functions like `wcslen`. This patch changes clang to always emit the
wchar_size module flag (it would only do so for ARM previously).
This also adds an `assert()` to ensure the LLVM defaults based on the
target triple are in sync with clang.
Differential Revision: https://reviews.llvm.org/D32982
llvm-svn: 303478
diff --git a/clang/test/CodeGen/wchar-size.c b/clang/test/CodeGen/wchar-size.c
new file mode 100644
index 0000000..38da462
--- /dev/null
+++ b/clang/test/CodeGen/wchar-size.c
@@ -0,0 +1,8 @@
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-llvm -o - %s | FileCheck %s -check-prefix=LONG-WCHAR
+// RUN: %clang_cc1 -triple x86_64-unknown-windows-msvc -emit-llvm -o - %s | FileCheck %s -check-prefix=SHORT-WCHAR
+// RUN: %clang_cc1 -triple x86_64-unknown-linux-gnu -emit-llvm -o - -fshort-wchar %s | FileCheck %s -check-prefix=SHORT-WCHAR
+// Note: -fno-short-wchar implies the target default is used; so there is no
+// need to test this separately here.
+
+// LONG-WCHAR: !{{[0-9]+}} = !{i32 {{[0-9]+}}, !"wchar_size", i32 4}
+// SHORT-WCHAR: !{{[0-9]+}} = !{i32 {{[0-9]+}}, !"wchar_size", i32 2}