[PATCH] D141206: [clang] [MinGW] Avoid adding <base>/include and <base>/lib when cross compiling

[Martin Storsjö via Phabricator via cfe-commits]

mstorsjo updated this revision to Diff 488182.
mstorsjo added a comment.

Updated with some testcases. This does test that the include directory is omitted when cross compiling, but those kinds of tests, which set up a simulated toolchain environment with symlinks, don't run on actual Windows - so it's not quite as easy to test the case that we actually do keep the unprefixed include directory on Windows. As this matches the current testing coverage status quo, I hope this is ok...


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D141206/new/

https://reviews.llvm.org/D141206

Files:
  clang/lib/Driver/ToolChains/MinGW.cpp
  clang/test/Driver/mingw-sysroot.cpp


Index: clang/test/Driver/mingw-sysroot.cpp
===================================================================
--- clang/test/Driver/mingw-sysroot.cpp
+++ clang/test/Driver/mingw-sysroot.cpp
@@ -31,6 +31,18 @@
 // CHECK_TESTROOT_GCC: "-internal-isystem" "[[BASE]]/testroot-gcc{{/|\\\\}}lib{{/|\\\\}}gcc{{/|\\\\}}x86_64-w64-mingw32{{/|\\\\}}10.2-posix{{/|\\\\}}include{{/|\\\\}}g++-v10"
 // CHECK_TESTROOT_GCC: "-internal-isystem" "[[BASE]]/testroot-gcc{{/|\\\\}}x86_64-w64-mingw32{{/|\\\\}}include"
 
+// This test is only executed on non-Windows systems, i.e. only when
+// cross compiling. Check that we don't add the tool root's plain include
+// directory to the path - this would end up including /usr/include for
+// cross toolchains installed in /usr.
+// CHECK_TESTROOT_GCC-NOT: "-internal-isystem" "[[BASE]]/testroot-gcc{{/|\\\\}}include"
+
+// If we pass --sysroot explicitly, then we do include <sysroot>/include
+// even when cross compiling.
+// RUN: %clang -target x86_64-w64-mingw32 -rtlib=platform -stdlib=libstdc++ --sysroot="%T/testroot-gcc" -c -### %s 2>&1 | FileCheck -check-prefix=CHECK_TESTROOT_GCC_EXPLICIT %s
+
+// CHECK_TESTROOT_GCC_EXPLICIT: "-internal-isystem" "{{[^"]+}}/testroot-gcc{{/|\\\\}}include"
+
 
 // If there's a matching sysroot next to the clang binary itself, prefer that
 // over a gcc in the path:
Index: clang/lib/Driver/ToolChains/MinGW.cpp
===================================================================
--- clang/lib/Driver/ToolChains/MinGW.cpp
+++ clang/lib/Driver/ToolChains/MinGW.cpp
@@ -348,6 +348,15 @@
                                          Exec, CmdArgs, Inputs, Output));
 }
 
+static bool isCrossCompiling(const llvm::Triple &T, bool RequireArchMatch) {
+  llvm::Triple HostTriple(llvm::Triple::normalize(LLVM_HOST_TRIPLE));
+  if (HostTriple.getOS() != llvm::Triple::Win32)
+    return true;
+  if (RequireArchMatch && HostTriple.getArch() != T.getArch())
+    return true;
+  return false;
+}
+
 // Simplified from Generic_GCC::GCCInstallationDetector::ScanLibDirForGCCTriple.
 static bool findGccVersion(StringRef LibDir, std::string &GccLibDir,
                            std::string &Ver,
@@ -487,7 +496,13 @@
   getFilePaths().push_back(
       (Base + SubdirName + llvm::sys::path::get_separator() + "mingw/lib").str());
 
-  getFilePaths().push_back(Base + "lib");
+  // Only include <base>/lib if we're not cross compiling (not even for
+  // windows->windows to a different arch), or if the sysroot has been set
+  // (where we presume the user has pointed it at an arch specific
+  // subdirectory).
+  if (!::isCrossCompiling(getTriple(), /*RequireArchMatch=*/true) ||
+      getDriver().SysRoot.size())
+    getFilePaths().push_back(Base + "lib");
 
   NativeLLVMSupport =
       Args.getLastArgValue(options::OPT_fuse_ld_EQ, CLANG_DEFAULT_LINKER)
@@ -649,7 +664,13 @@
   addSystemInclude(DriverArgs, CC1Args,
                    Base + SubdirName + llvm::sys::path::get_separator() + "usr/include");
 
-  addSystemInclude(DriverArgs, CC1Args, Base + "include");
+  // Only include <base>/include if we're not cross compiling (but do allow it
+  // if we're on Windows and building for Windows on another architecture),
+  // or if the sysroot has been set (where we presume the user has pointed it
+  // at an arch specific subdirectory).
+  if (!::isCrossCompiling(getTriple(), /*RequireArchMatch=*/false) ||
+      getDriver().SysRoot.size())
+    addSystemInclude(DriverArgs, CC1Args, Base + "include");
 }
 
 void toolchains::MinGW::addClangTargetOptions(


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D141206.488182.patch
Type: text/x-patch
Size: 3538 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/cfe-commits/attachments/20230111/9334a7a2/attachment-0001.bin>