ohos: fix ohos.c test case error with LLVM_ENABLE_PER_TARGET_RUNTIME_…

[phuang]

…DIR=OFF

The problem is because libclang_rt.builtins-{arch}.a for all the arches will be installed into the same folder with old compiler rt layout (LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF) and OHOS driver will get a wrong library in this case. To fix the problem, -ohos suffix will be added to the ohos builtin libraries search path.

Note: OHOS driver doesn't support the old layout, compiler-rt for ${arch}-linux-unknown-ohos targets have to be built with
LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON

[llvmbot]

@llvm/pr-subscribers-clang

Author: Peng Huang (phuang)

Changes

…DIR=OFF

The problem is because libclang_rt.builtins-{arch}.a for all the arches will be installed into the same folder with old compiler rt layout (LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF) and OHOS driver will get a wrong library in this case. To fix the problem, -ohos suffix will be added to the ohos builtin libraries search path.

Note: OHOS driver doesn't support the old layout, compiler-rt for ${arch}-linux-unknown-ohos targets have to be built with
LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON

---

Full diff: https://github.com/llvm/llvm-project/pull/121484.diff

1 Files Affected:

• (modified) clang/lib/Driver/ToolChain.cpp (+5-1)

diff --git a/clang/lib/Driver/ToolChain.cpp b/clang/lib/Driver/ToolChain.cpp
index 9f174fbda398b5..06ff0918245ea4 100644
--- a/clang/lib/Driver/ToolChain.cpp
+++ b/clang/lib/Driver/ToolChain.cpp
@@ -745,7 +745,11 @@ std::string ToolChain::buildCompilerRTBasename(const llvm::opt::ArgList &Args,
   std::string ArchAndEnv;
   if (AddArch) {
     StringRef Arch = getArchNameForCompilerRTLib(*this, Args);
-    const char *Env = TT.isAndroid() ? "-android" : "";
+    const char *Env = "";
+    if (TT.isAndroid())
+      Env = "-android";
+    else if (TT.isOHOSFamily())
+      Env = "-ohos";
     ArchAndEnv = ("-" + Arch + Env).str();
   }
   return (Prefix + Twine("clang_rt.") + Component + ArchAndEnv + Suffix).str();

[llvmbot]

@llvm/pr-subscribers-clang-driver

Author: Peng Huang (phuang)

Changes

…DIR=OFF

The problem is because libclang_rt.builtins-{arch}.a for all the arches will be installed into the same folder with old compiler rt layout (LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF) and OHOS driver will get a wrong library in this case. To fix the problem, -ohos suffix will be added to the ohos builtin libraries search path.

Note: OHOS driver doesn't support the old layout, compiler-rt for ${arch}-linux-unknown-ohos targets have to be built with
LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON

---

Full diff: https://github.com/llvm/llvm-project/pull/121484.diff

1 Files Affected:

• (modified) clang/lib/Driver/ToolChain.cpp (+5-1)

diff --git a/clang/lib/Driver/ToolChain.cpp b/clang/lib/Driver/ToolChain.cpp
index 9f174fbda398b5..06ff0918245ea4 100644
--- a/clang/lib/Driver/ToolChain.cpp
+++ b/clang/lib/Driver/ToolChain.cpp
@@ -745,7 +745,11 @@ std::string ToolChain::buildCompilerRTBasename(const llvm::opt::ArgList &Args,
   std::string ArchAndEnv;
   if (AddArch) {
     StringRef Arch = getArchNameForCompilerRTLib(*this, Args);
-    const char *Env = TT.isAndroid() ? "-android" : "";
+    const char *Env = "";
+    if (TT.isAndroid())
+      Env = "-android";
+    else if (TT.isOHOSFamily())
+      Env = "-ohos";
     ArchAndEnv = ("-" + Arch + Env).str();
   }
   return (Prefix + Twine("clang_rt.") + Component + ArchAndEnv + Suffix).str();

[carlocab]

Note: OHOS driver doesn't support the old layout, compiler-rt for ${arch}-linux-unknown-ohos targets have to be built with LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON

Can we make cmake error out if you try to build for *-linux-unknown-ohos with LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF?

[phuang]

Note: OHOS driver doesn't support the old layout, compiler-rt for ${arch}-linux-unknown-ohos targets have to be built with LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON

Can we make cmake error out if you try to build for *-linux-unknown-ohos with LLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF?

Sure. I will try adding it.
And one question: will llvm deprecate the old layout? should we consider adding the old layout support for ohos?

[carlocab]

And one question: will llvm deprecate the old layout?

There was some desire to, but it seems to have fizzled out: https://discourse.llvm.org/t/rfc-time-to-drop-legacy-runtime-paths/64628

I imagine it'll happen eventually, but it will probably take a while.

should we consider adding the old layout support for ohos?

I don't know enough about OHOS and its users to be able to say. If you're not sure: I suggest leaving out support for now, and someone who needs it can contribute support for it. But if we do leave support out: good error messages for users who happen to try to use/build it in the wrong configuration are probably essential.

[phuang]

To add this cmake configure error, where should I look at? any hint?

[phuang]

Updated the cmake script to output error message if LLVM_ENABLE_PER_TARGET_RUNTIME_DIR is OFF for ohos targets.

[MaskRay]

We can disable the test on -DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=OFF layouts, but I don't find a lit feature that.

The usual way is to create a compiler-rt file hierarchy under Inputs. Just fd libclang_rt.builtins.a for some examples.

[MaskRay]

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