[PATCH] D85324: [SystemZ][z/OS] Add z/OS Target and define macros

[Hubert Tong via Phabricator via cfe-commits]

hubert.reinterpretcast added inline comments.


================
Comment at: clang/lib/Basic/Targets/OSTargets.h:730
+                    MacroBuilder &Builder) const override {
+    Builder.defineMacro("_LONG_LONG");
+    Builder.defineMacro("_OPEN_DEFAULT");
----------------
The comment from https://reviews.llvm.org/D85324?id=283290#inline-786609 applies here as well. `_LONG_LONG` should not be defined under `-std=c89 -pedantic-errors` or `-std=c89 -Werror=long-long`.


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Comment at: clang/lib/Basic/Targets/OSTargets.h:753
+      Builder.defineMacro("__DLL__");
+      // Macro __wchar_t is defined so wchar_t data type
+      // is not declared as a typedef in system headers.
----------------
s/so wchar_t/so that the wchar_t/;


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Comment at: clang/lib/Basic/Targets/OSTargets.h:755
+      // is not declared as a typedef in system headers.
+      Builder.defineMacro("__wchar_t");
+      // XOPEN_SOURCE=600 is required to build libcxx.
----------------
The corresponding AIX code checks for `-Xclang -fno-wchar`. The behaviour of `stddef.h` differs when using `-fno-wchar` between AIX and Linux though. Linux suppresses the typedef based on `__cplusplus`. Arguably, the OS header difference should not really factor into whether the compiler defines a macro that indicates the presence of a `wchar_t` fundamental type.


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Comment at: clang/lib/Basic/Targets/OSTargets.h:766
+    if (Opts.C11 || Opts.GNUMode) {
+      Builder.defineMacro("__IBM_UTF_LITERAL");
+      Builder.defineMacro("__IBMC_NORETURN");
----------------
The GNU extension modes do not cause u-prefixed, etc. string literals to be accepted where the base language level would treat the prefix as a separate identifier. Also noting here that the previous comment from https://reviews.llvm.org/D85324?id=283290#inline-786628 was made based on noting that `__IBM_UTF_LITERAL` is defined by the XL compiler in the appropriate C++ modes.


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Comment at: clang/lib/Basic/Targets/OSTargets.h:767
+      Builder.defineMacro("__IBM_UTF_LITERAL");
+      Builder.defineMacro("__IBMC_NORETURN");
+    }
----------------
I would expect that the Clang implementation of the "IBM-style" feature test macros would behave similarly to the native feature testing in Clang. That is, `__IBMC_NORETURN` is defined when `_Noreturn` is available as an extension. `_Noreturn` is available as an "orthogonal" or "conforming" extension in modes such as `-std=c89` and `-std=c++03`. The extension is disabled via warnings-as-errors.


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Comment at: clang/lib/Basic/Targets/OSTargets.h:770
+
+    if (Opts.CPlusPlus11 || (Opts.GNUMode && Opts.CPlusPlus)) {
+      Builder.defineMacro("__IBM_CHAR16_T__");
----------------
See comment above re: GNU extension modes not enabling u-prefixed, etc. literals.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D85324/new/

https://reviews.llvm.org/D85324