[5.9] pass -fno-omit-frame-pointer in support of new backtracer (#7042) (#7049)

5.9 cherry pick of #7042

Author: tomerd

Sources/Build/BuildDescription/ClangTargetBuildDescription.swift

@@ -294,6 +294,17 @@ public final class ClangTargetBuildDescription {
             args += self.buildParameters.flags.cxxCompilerFlags
         }
 
+        // rdar://117578677
+        // Pass -fno-omit-frame-pointer to support backtraces
+        // this can be removed once the backtracer uses DWARF instead of frame pointers
+        if let omitFramePointers = self.buildParameters.omitFramePointers {
+            if omitFramePointers {
+                args += ["-fomit-frame-pointer"]
+            } else {
+                args += ["-fno-omit-frame-pointer"]
+            }
+        }
+
         // Pass default include paths from the toolchain.
         for includeSearchPath in self.buildParameters.toolchain.includeSearchPaths {
             args += ["-I", includeSearchPath.pathString]

Sources/Build/BuildDescription/SwiftTargetBuildDescription.swift

@@ -530,6 +530,17 @@ public final class SwiftTargetBuildDescription {
 
         args += self.packageNameArgumentIfSupported(with: self.package, packageAccess: self.target.packageAccess)
         args += try self.macroArguments()
+        
+        // rdar://117578677
+        // Pass -fno-omit-frame-pointer to support backtraces
+        // this can be removed once the backtracer uses DWARF instead of frame pointers
+        if let omitFramePointers = self.buildParameters.omitFramePointers {
+            if omitFramePointers {
+                args += ["-Xcc", "-fomit-frame-pointer"]
+            } else {
+                args += ["-Xcc", "-fno-omit-frame-pointer"]
+            }
+        }
 
         return args
     }

Sources/CoreCommands/Options.swift

@@ -470,6 +470,11 @@ public struct BuildOptions: ParsableArguments {
     )
     public var testEntryPointPath: AbsolutePath?
 
+    // Whether to omit frame pointers
+    // this can be removed once the backtracer uses DWARF instead of frame pointers
+    @Flag(inversion: .prefixedNo,  help: .hidden)
+    public var omitFramePointers: Bool? = nil
+
     // @Flag works best when there is a default value present
     // if true, false aren't enough and a third state is needed
     // nil should not be the goto. Instead create an enum

Sources/CoreCommands/SwiftTool.swift

@@ -695,6 +695,7 @@ public final class SwiftTool {
             isXcodeBuildSystemEnabled: options.build.buildSystem == .xcode,
             forceTestDiscovery: options.build.enableTestDiscovery, // backwards compatibility, remove with --enable-test-discovery
             testEntryPointPath: options.build.testEntryPointPath,
+            omitFramePointers: options.build.omitFramePointers,
             explicitTargetDependencyImportCheckingMode: options.build.explicitTargetDependencyImportCheck.modeParameter,
             linkerDeadStrip: options.linker.linkerDeadStrip,
             verboseOutput: self.logLevel <= .info

Sources/SPMBuildCore/BuildParameters.swift

@@ -215,6 +215,9 @@ public struct BuildParameters: Encodable {
     /// The style of test product to produce.
     public var testProductStyle: TestProductStyle
 
+    /// Whether to omit or preserver frame pointers
+    public var omitFramePointers: Bool?
+
     /// Whether to disable dead code stripping by the linker
     public var linkerDeadStrip: Bool
 
@@ -247,6 +250,7 @@ public struct BuildParameters: Encodable {
         enableTestability: Bool? = nil,
         forceTestDiscovery: Bool = false,
         testEntryPointPath: AbsolutePath? = nil,
+        omitFramePointers: Bool? = nil,
         explicitTargetDependencyImportCheckingMode: TargetDependencyImportCheckingMode = .none,
         linkerDeadStrip: Bool = true,
         colorizedOutput: Bool = false,
@@ -287,6 +291,7 @@ public struct BuildParameters: Encodable {
             explicitlyEnabledDiscovery: forceTestDiscovery,
             explicitlySpecifiedPath: testEntryPointPath
         )
+        self.omitFramePointers = omitFramePointers ?? (triple.isLinux() ? false : nil)
         self.explicitTargetDependencyImportCheckingMode = explicitTargetDependencyImportCheckingMode
         self.linkerDeadStrip = linkerDeadStrip
         self.colorizedOutput = colorizedOutput

Tests/BuildTests/BuildPlanTests.swift

@@ -1190,6 +1190,11 @@ final class BuildPlanTests: XCTestCase {
 #if !os(Windows)    // FIXME(5473) - modules flags on Windows dropped
         args += ["-fmodules-cache-path=\(buildPath.appending(components: "ModuleCache"))"]
 #endif
+
+        if hostTriple.isLinux() {
+            args += ["-fno-omit-frame-pointer"]
+        }
+
         XCTAssertEqual(try ext.basicArguments(isCXX: false), args)
         XCTAssertEqual(try ext.objects, [buildPath.appending(components: "extlib.build", "extlib.c.o")])
         XCTAssertEqual(ext.moduleMap, buildPath.appending(components: "extlib.build", "module.modulemap"))
@@ -1222,6 +1227,11 @@ final class BuildPlanTests: XCTestCase {
 #if !os(Windows)    // FIXME(5473) - modules flags on Windows dropped
         args += ["-fmodules-cache-path=\(buildPath.appending(components: "ModuleCache"))"]
 #endif
+
+        if hostTriple.isLinux() {
+            args += ["-fno-omit-frame-pointer"]
+        }
+
         XCTAssertEqual(try exe.basicArguments(isCXX: false), args)
         XCTAssertEqual(try exe.objects, [buildPath.appending(components: "exe.build", "main.c.o")])
         XCTAssertEqual(exe.moduleMap, nil)
@@ -1453,7 +1463,7 @@ final class BuildPlanTests: XCTestCase {
         XCTAssertMatch(contents, .contains(#"-std=c++1z","-c","\#(Pkg.appending(components: "Sources", "lib", "libx.cpp").escapedPathString())"#))
 
         let swiftInteropLib = try result.target(for: "swiftInteropLib").swiftTarget().compileArguments()
-        XCTAssertMatch(swiftInteropLib, [.anySequence, "-cxx-interoperability-mode=default", "-Xcc", "-std=c++1z", .end])
+        XCTAssertMatch(swiftInteropLib, [.anySequence, "-cxx-interoperability-mode=default", "-Xcc", "-std=c++1z", .anySequence])
         let swiftLib = try result.target(for: "swiftLib").swiftTarget().compileArguments()
         XCTAssertNoMatch(swiftLib, [.anySequence, "-Xcc", "-std=c++1z", .anySequence])
     }
@@ -1516,6 +1526,11 @@ final class BuildPlanTests: XCTestCase {
 #if !os(Windows)    // FIXME(5473) - modules flags on Windows dropped
         args += ["-fmodules-cache-path=\(buildPath.appending(components: "ModuleCache"))"]
 #endif
+
+        if hostTriple.isLinux() {
+            args += ["-fno-omit-frame-pointer"]
+        }
+
         XCTAssertEqual(try lib.basicArguments(isCXX: false), args)
         XCTAssertEqual(try lib.objects, [buildPath.appending(components: "lib.build", "lib.c.o")])
         XCTAssertEqual(lib.moduleMap, buildPath.appending(components: "lib.build", "module.modulemap"))
@@ -2480,6 +2495,11 @@ final class BuildPlanTests: XCTestCase {
 #if !os(Windows)    // FIXME(5473) - modules flags on Windows dropped
         expectedExeBasicArgs += ["-fmodules-cache-path=\(buildPath.appending(components: "ModuleCache"))"]
 #endif
+
+        if triple.isLinux() {
+            expectedExeBasicArgs += ["-fno-omit-frame-pointer"]
+        }
+
         XCTAssertEqual(try exe.basicArguments(isCXX: false), expectedExeBasicArgs)
         XCTAssertEqual(try exe.objects, [buildPath.appending(components: "exe.build", "main.c.o")])
         XCTAssertEqual(exe.moduleMap, nil)
@@ -2498,6 +2518,11 @@ final class BuildPlanTests: XCTestCase {
         if shouldHaveModules {
             expectedLibBasicArgs += ["-fmodules-cache-path=\(buildPath.appending(components: "ModuleCache"))"]
         }
+
+        if triple.isLinux() {
+            expectedLibBasicArgs += ["-fno-omit-frame-pointer"]
+        }
+
         XCTAssertEqual(try lib.basicArguments(isCXX: true), expectedLibBasicArgs)
 
         XCTAssertEqual(try lib.objects, [buildPath.appending(components: "lib.build", "lib.cpp.o")])
@@ -3382,21 +3407,71 @@ final class BuildPlanTests: XCTestCase {
             let result = try createResult(for: .x86_64Linux)
 
             let dep = try result.target(for: "t1").swiftTarget().compileArguments()
-            XCTAssertMatch(dep, [.anySequence, "-DDEP", .end])
+            XCTAssertMatch(dep, [.anySequence, "-DDEP", "-Xcc", "-fno-omit-frame-pointer", .end])
 
             let cbar = try result.target(for: "cbar").clangTarget().basicArguments(isCXX: false)
-            XCTAssertMatch(cbar, [.anySequence, "-DCCC=2", "-I\(A.appending(components: "Sources", "cbar", "Sources", "headers"))", "-I\(A.appending(components: "Sources", "cbar", "Sources", "cppheaders"))", "-Icfoo", "-L", "cbar", "-Icxxfoo", "-L", "cxxbar", .end])
+            XCTAssertMatch(cbar, [.anySequence, "-DCCC=2", "-I\(A.appending(components: "Sources", "cbar", "Sources", "headers"))", "-I\(A.appending(components: "Sources", "cbar", "Sources", "cppheaders"))", "-Icfoo", "-L", "cbar", "-Icxxfoo", "-L", "cxxbar", "-fno-omit-frame-pointer", .end])
 
             let bar = try result.target(for: "bar").swiftTarget().compileArguments()
-            XCTAssertMatch(bar, [.anySequence, "-DLINUX", "-Isfoo", "-L", "sbar", "-cxx-interoperability-mode=default", "-enable-upcoming-feature", "BestFeature", .end])
+            XCTAssertMatch(bar, [.anySequence, "-DLINUX", "-Isfoo", "-L", "sbar", "-cxx-interoperability-mode=default", "-enable-upcoming-feature", "BestFeature", "-Xcc", "-fno-omit-frame-pointer", .end])
 
             let exe = try result.target(for: "exe").swiftTarget().compileArguments()
-            XCTAssertMatch(exe, [.anySequence, "-DFOO", .end])
+            XCTAssertMatch(exe, [.anySequence, "-DFOO", "-Xcc", "-fno-omit-frame-pointer", .end])
 
             let linkExe = try result.buildProduct(for: "exe").linkArguments()
             XCTAssertMatch(linkExe, [.anySequence, "-lsqlite3", "-llibz", "-framework", "best", "-Ilfoo", "-L", "lbar", .end])
         }
 
+        // omit frame pointers explicitly set to true
+        do {
+            let result = try BuildPlanResult(plan: BuildPlan(
+                buildParameters: mockBuildParameters(
+                    destinationTriple: .x86_64Linux,
+                    omitFramePointers: true
+                ),
+                graph: graph,
+                fileSystem: fs,
+                observabilityScope: observability.topScope
+            ))
+
+            let dep = try result.target(for: "t1").swiftTarget().compileArguments()
+            XCTAssertMatch(dep, [.anySequence, "-DDEP", .anySequence])
+
+            let cbar = try result.target(for: "cbar").clangTarget().basicArguments(isCXX: false)
+            XCTAssertMatch(cbar, [.anySequence, "-DCCC=2", "-I\(A.appending(components: "Sources", "cbar", "Sources", "headers"))", "-I\(A.appending(components: "Sources", "cbar", "Sources", "cppheaders"))", "-Icfoo", "-L", "cbar", "-Icxxfoo", "-L", "cxxbar", "-fomit-frame-pointer", .end])
+
+            let bar = try result.target(for: "bar").swiftTarget().compileArguments()
+            XCTAssertMatch(bar, [.anySequence, "-DLINUX", "-Isfoo", "-L", "sbar", "-cxx-interoperability-mode=default", "-enable-upcoming-feature", "BestFeature", "-Xcc", "-fomit-frame-pointer", .end])
+
+            let exe = try result.target(for: "exe").swiftTarget().compileArguments()
+            XCTAssertMatch(exe, [.anySequence, "-DFOO", "-Xcc", "-fomit-frame-pointer", .end])
+        }
+
+        // omit frame pointers explicitly set to false
+        do {
+            let result = try BuildPlanResult(plan: BuildPlan(
+                buildParameters: mockBuildParameters(
+                    destinationTriple: .x86_64Linux,
+                    omitFramePointers: false
+                ),
+                graph: graph,
+                fileSystem: fs,
+                observabilityScope: observability.topScope
+            ))
+
+            let dep = try result.target(for: "t1").swiftTarget().compileArguments()
+            XCTAssertMatch(dep, [.anySequence, "-DDEP", .anySequence])
+
+            let cbar = try result.target(for: "cbar").clangTarget().basicArguments(isCXX: false)
+            XCTAssertMatch(cbar, [.anySequence, "-DCCC=2", "-I\(A.appending(components: "Sources", "cbar", "Sources", "headers"))", "-I\(A.appending(components: "Sources", "cbar", "Sources", "cppheaders"))", "-Icfoo", "-L", "cbar", "-Icxxfoo", "-L", "cxxbar", "-fno-omit-frame-pointer", .end])
+
+            let bar = try result.target(for: "bar").swiftTarget().compileArguments()
+            XCTAssertMatch(bar, [.anySequence, "-DLINUX", "-Isfoo", "-L", "sbar", "-cxx-interoperability-mode=default", "-enable-upcoming-feature", "BestFeature", "-Xcc", "-fno-omit-frame-pointer", .end])
+
+            let exe = try result.target(for: "exe").swiftTarget().compileArguments()
+            XCTAssertMatch(exe, [.anySequence, "-DFOO", "-Xcc", "-fno-omit-frame-pointer", .end])
+        }
+
         do {
             let result = try createResult(for: .macOS)
 

Tests/BuildTests/MockBuildTestHelper.swift

@@ -76,7 +76,8 @@ func mockBuildParameters(
     destinationTriple: Basics.Triple = hostTriple,
     indexStoreMode: BuildParameters.IndexStoreMode = .off,
     useExplicitModuleBuild: Bool = false,
-    linkerDeadStrip: Bool = true
+    linkerDeadStrip: Bool = true,
+    omitFramePointers: Bool? = nil
 ) -> BuildParameters {
     return try! BuildParameters(
         dataPath: buildPath,
@@ -91,6 +92,7 @@ func mockBuildParameters(
         canRenameEntrypointFunctionName: canRenameEntrypointFunctionName,
         indexStoreMode: indexStoreMode,
         useExplicitModuleBuild: useExplicitModuleBuild,
+        omitFramePointers: omitFramePointers,
         linkerDeadStrip: linkerDeadStrip
     )
 }