[clang-scan-deps] Infer the tool locations from PATH (#108539)

mstorsjo · tru · commit 2b6c23303f7c · 2024-10-01T08:53:03.000+02:00
This allows the clang driver to know which tool is meant to be executed, which allows the clang driver to load the right clang config files, and allows clang to find colocated sysroots. This makes sure that doing `clang-scan-deps -- <tool> ...` looks up things in the same way as if one just would execute `<tool> ...`, when `<tool>` isn't an absolute or relative path. (cherry picked from commit a26ec54)
diff --git a/clang/include/clang/Tooling/CompilationDatabase.h b/clang/include/clang/Tooling/CompilationDatabase.h
@@ -234,6 +234,12 @@ std::unique_ptr<CompilationDatabase>
 std::unique_ptr<CompilationDatabase>
 inferTargetAndDriverMode(std::unique_ptr<CompilationDatabase> Base);
 
+/// Returns a wrapped CompilationDatabase that will transform argv[0] to an
+/// absolute path, if it currently is a plain tool name, looking it up in
+/// PATH.
+std::unique_ptr<CompilationDatabase>
+inferToolLocation(std::unique_ptr<CompilationDatabase> Base);
+
 /// Returns a wrapped CompilationDatabase that will expand all rsp(response)
 /// files on commandline returned by underlying database.
 std::unique_ptr<CompilationDatabase>
diff --git a/clang/lib/Tooling/CMakeLists.txt b/clang/lib/Tooling/CMakeLists.txt
@@ -25,6 +25,7 @@ add_clang_library(clangTooling
   GuessTargetAndModeCompilationDatabase.cpp
   InterpolatingCompilationDatabase.cpp
   JSONCompilationDatabase.cpp
+  LocateToolCompilationDatabase.cpp
   Refactoring.cpp
   RefactoringCallbacks.cpp
   StandaloneExecution.cpp
diff --git a/clang/lib/Tooling/LocateToolCompilationDatabase.cpp b/clang/lib/Tooling/LocateToolCompilationDatabase.cpp
@@ -0,0 +1,71 @@
+//===- GuessTargetAndModeCompilationDatabase.cpp --------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Tooling/CompilationDatabase.h"
+#include "clang/Tooling/Tooling.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/Program.h"
+#include <memory>
+
+namespace clang {
+namespace tooling {
+
+namespace {
+class LocationAdderDatabase : public CompilationDatabase {
+public:
+  LocationAdderDatabase(std::unique_ptr<CompilationDatabase> Base)
+      : Base(std::move(Base)) {
+    assert(this->Base != nullptr);
+  }
+
+  std::vector<std::string> getAllFiles() const override {
+    return Base->getAllFiles();
+  }
+
+  std::vector<CompileCommand> getAllCompileCommands() const override {
+    return addLocation(Base->getAllCompileCommands());
+  }
+
+  std::vector<CompileCommand>
+  getCompileCommands(StringRef FilePath) const override {
+    return addLocation(Base->getCompileCommands(FilePath));
+  }
+
+private:
+  std::vector<CompileCommand>
+  addLocation(std::vector<CompileCommand> Cmds) const {
+    for (auto &Cmd : Cmds) {
+      if (Cmd.CommandLine.empty())
+        continue;
+      std::string &Driver = Cmd.CommandLine.front();
+      // If the driver name already is absolute, we don't need to do anything.
+      if (llvm::sys::path::is_absolute(Driver))
+        continue;
+      // If the name is a relative path, like bin/clang, we assume it's
+      // possible to resolve it and don't do anything about it either.
+      if (llvm::any_of(Driver,
+                       [](char C) { return llvm::sys::path::is_separator(C); }))
+        continue;
+      auto Absolute = llvm::sys::findProgramByName(Driver);
+      // If we found it in path, update the entry in Cmd.CommandLine
+      if (Absolute && llvm::sys::path::is_absolute(*Absolute))
+        Driver = std::move(*Absolute);
+    }
+    return Cmds;
+  }
+  std::unique_ptr<CompilationDatabase> Base;
+};
+} // namespace
+
+std::unique_ptr<CompilationDatabase>
+inferToolLocation(std::unique_ptr<CompilationDatabase> Base) {
+  return std::make_unique<LocationAdderDatabase>(std::move(Base));
+}
+
+} // namespace tooling
+} // namespace clang
diff --git a/clang/test/ClangScanDeps/modules-extern-submodule.c b/clang/test/ClangScanDeps/modules-extern-submodule.c
@@ -112,8 +112,7 @@ module third {}
 // CHECK:                  "-fmodule-map-file=[[PREFIX]]/first/first/module.modulemap",
 // CHECK:                  "-fmodule-file=first=[[PREFIX]]/cache/{{.*}}/first-{{.*}}.pcm",
 // CHECK:                ],
-// CHECK-NEXT:           "executable": "clang",
-// CHECK-NEXT:           "file-deps": [
+// CHECK:                "file-deps": [
 // CHECK-NEXT:             "[[PREFIX]]/tu.m"
 // CHECK-NEXT:           ],
 // CHECK-NEXT:           "input-file": "[[PREFIX]]/tu.c"
diff --git a/clang/test/ClangScanDeps/modules-full-output-tu-order.c b/clang/test/ClangScanDeps/modules-full-output-tu-order.c
@@ -35,8 +35,7 @@
 // CHECK:                  "-D"
 // CHECK-NEXT:             "ONE"
 // CHECK:                ],
-// CHECK-NEXT:           "executable": "clang",
-// CHECK-NEXT:           "file-deps": [
+// CHECK:                "file-deps": [
 // CHECK-NEXT:             "[[PREFIX]]/tu.c"
 // CHECK-NEXT:           ],
 // CHECK-NEXT:           "input-file": "[[PREFIX]]/tu.c"
@@ -52,8 +51,7 @@
 // CHECK:                  "-D"
 // CHECK-NEXT:             "TWO"
 // CHECK:                ],
-// CHECK-NEXT:           "executable": "clang",
-// CHECK-NEXT:           "file-deps": [
+// CHECK:                "file-deps": [
 // CHECK-NEXT:             "[[PREFIX]]/tu.c"
 // CHECK-NEXT:           ],
 // CHECK-NEXT:           "input-file": "[[PREFIX]]/tu.c"
diff --git a/clang/test/ClangScanDeps/modules-has-include-umbrella-header.c b/clang/test/ClangScanDeps/modules-has-include-umbrella-header.c
@@ -64,8 +64,7 @@ module Dependency { header "dependency.h" }
 // CHECK:                ],
 // CHECK-NEXT:           "command-line": [
 // CHECK:                ],
-// CHECK-NEXT:           "executable": "clang",
-// CHECK-NEXT:           "file-deps": [
+// CHECK:                "file-deps": [
 // CHECK-NEXT:             "[[PREFIX]]/tu.c"
 // CHECK-NEXT:           ],
 // CHECK-NEXT:           "input-file": "[[PREFIX]]/tu.c"
diff --git a/clang/test/ClangScanDeps/modules-header-sharing.m b/clang/test/ClangScanDeps/modules-header-sharing.m
@@ -77,8 +77,7 @@
 // CHECK:                  "-fmodule-map-file=[[PREFIX]]/frameworks/A.framework/Modules/module.modulemap",
 // CHECK:                  "-fmodule-name=A",
 // CHECK:                ],
-// CHECK-NEXT:           "executable": "clang",
-// CHECK-NEXT:           "file-deps": [
+// CHECK:                "file-deps": [
 // CHECK-NEXT:             "[[PREFIX]]/tu.m",
 // CHECK-NEXT:             "[[PREFIX]]/shared/H.h"
 // CHECK-NEXT:           ],
diff --git a/clang/test/ClangScanDeps/modules-implementation-module-map.c b/clang/test/ClangScanDeps/modules-implementation-module-map.c
@@ -27,8 +27,7 @@ framework module FWPrivate { header "private.h" }
 // CHECK:                "-fmodule-map-file=[[PREFIX]]/frameworks/FW.framework/Modules/module.private.modulemap",
 // CHECK:                "-fmodule-name=FWPrivate",
 // CHECK:              ],
-// CHECK-NEXT:         "executable": "clang",
-// CHECK-NEXT:         "file-deps": [
+// CHECK:              "file-deps": [
 // CHECK-NEXT:           "[[PREFIX]]/tu.m"
 // CHECK-NEXT:         ],
 // CHECK-NEXT:         "input-file": "[[PREFIX]]/tu.m"
diff --git a/clang/test/ClangScanDeps/modules-implementation-private.m b/clang/test/ClangScanDeps/modules-implementation-private.m
@@ -62,8 +62,7 @@
 // CHECK-NEXT:           ],
 // CHECK-NEXT:           "command-line": [
 // CHECK:                ],
-// CHECK-NEXT:           "executable": "clang",
-// CHECK-NEXT:           "file-deps": [
+// CHECK:                "file-deps": [
 // CHECK-NEXT:             "[[PREFIX]]/tu.m",
 // CHECK-NEXT:             "[[PREFIX]]/frameworks/FW.framework/PrivateHeaders/Missed.h",
 // CHECK-NEXT:             "[[PREFIX]]/frameworks/FW.framework/Headers/FW.h"
diff --git a/clang/test/ClangScanDeps/modules-priv-fw-from-pub.m b/clang/test/ClangScanDeps/modules-priv-fw-from-pub.m
@@ -110,8 +110,7 @@
 // CHECK-NEXT:           ],
 // CHECK-NEXT:           "command-line": [
 // CHECK:                ],
-// CHECK-NEXT:           "executable": "clang",
-// CHECK-NEXT:           "file-deps": [
+// CHECK:                "file-deps": [
 // CHECK-NEXT:             "[[PREFIX]]/tu.m"
 // CHECK-NEXT:           ],
 // CHECK-NEXT:           "input-file": "[[PREFIX]]/tu.m"
diff --git a/clang/test/ClangScanDeps/resolve-executable-path.c b/clang/test/ClangScanDeps/resolve-executable-path.c
@@ -0,0 +1,32 @@
+// UNSUPPORTED: system-windows
+
+// Check that we expand the executable name to an absolute path, when invoked
+// with a plain executable name, which is implied to be found in PATH.
+// REQUIRES: x86-registered-target
+
+// RUN: rm -rf %t
+// RUN: mkdir -p %t/bin
+// RUN: ln -s %clang %t/bin/x86_64-w64-mingw32-clang
+// RUN: split-file %s %t
+// RUN: sed -e "s|DIR|%/t|g" %t/cdb.json.in > %t/cdb.json
+
+// Check that we can deduce this both when using a compilation database, and when using
+// a literal command line.
+
+// RUN: env "PATH=%t/bin:%PATH%" clang-scan-deps -format experimental-full -compilation-database %t/cdb.json | FileCheck %s -DBASE=%/t
+
+// RUN: env "PATH=%t/bin:%PATH%" clang-scan-deps -format experimental-full -- x86_64-w64-mingw32-clang %t/source.c -o %t/source.o | FileCheck %s -DBASE=%/t
+
+// CHECK: "executable": "[[BASE]]/bin/x86_64-w64-mingw32-clang"
+
+//--- cdb.json.in
+[
+  {
+    "directory": "DIR"
+    "command": "x86_64-w64-mingw32-clang -c DIR/source.c -o DIR/source.o"
+    "file": "DIR/source.c"
+  },
+]
+
+//--- source.c
+void func(void) {}
diff --git a/clang/tools/clang-scan-deps/ClangScanDeps.cpp b/clang/tools/clang-scan-deps/ClangScanDeps.cpp
@@ -815,6 +815,8 @@ int clang_scan_deps_main(int argc, char **argv, const llvm::ToolContext &) {
 
   Compilations = inferTargetAndDriverMode(std::move(Compilations));
 
+  Compilations = inferToolLocation(std::move(Compilations));
+
   // The command options are rewritten to run Clang in preprocessor only mode.
   auto AdjustingCompilations =
       std::make_unique<tooling::ArgumentsAdjustingCompilations>(
