[clang-ifs] Clang Interface Stubs, first version.

Clang interface stubs (previously referred to as clang-ifsos) is a new frontend
action in clang that allows the generation of stub files that contain mangled
name info that can be used to produce a stub library. These stub libraries can
be useful for breaking up build dependencies and controlling access to a
library's internal symbols. Generation of these stubs can be invoked by:

clang -fvisibility=<visibility> -emit-interface-stubs \
                                -interface-stub-version=<interface format>

Notice that -fvisibility (along with use of visibility attributes) can be used
to control what symbols get generated. Currently the interface format is
experimental but there are a wide range of possibilities here.

Differential Revision: https://reviews.llvm.org/D60974

llvm-svn: 363626

1 files changed, 27 insertions, 0 deletions

diff --git a/clang/test/InterfaceStubs/weak.cpp b/clang/test/InterfaceStubs/weak.cpp
new file mode 100644
index 00000000000..e089225b5d6
--- /dev/null
+++ b/clang/test/InterfaceStubs/weak.cpp
@@ -0,0 +1,27 @@
+// RUN: %clang -target x86_64-linux-gnu -o - -emit-interface-stubs \
+// RUN: -interface-stub-version=experimental-tapi-elf-v1 %s | \
+// RUN: FileCheck %s
+
+// RUN: %clang -target x86_64-linux-gnu -o - -emit-interface-stubs \
+// RUN: -interface-stub-version=experimental-yaml-elf-v1 %s | \
+// RUN: FileCheck --check-prefix=CHECK-YAML %s
+
+// RUN: %clang -target x86_64-unknown-linux-gnu -o - -c %s | llvm-nm - 2>&1 | \
+// RUN: FileCheck -check-prefix=CHECK-SYMBOLS %s
+
+// CHECK: Symbols:
+// CHECK-DAG:  _Z8weakFuncv: { Type: Func, Weak: true }
+// CHECK-DAG:  _Z10strongFuncv: { Type: Func }
+
+// CHECK-YAML: Symbols:
+// CHECK-YAML-DAG:   - Name:            _Z8weakFuncv
+// CHECK-YAML-DAG:     Type:            STT_FUNC
+// CHECK-YAML-DAG:     Binding:         STB_WEAK
+// CHECK-YAML-DAG:   - Name:            _Z10strongFuncv
+// CHECK-YAML-DAG:     Type:            STT_FUNC
+// CHECK-YAML-DAG:     Binding:         STB_GLOBAL
+
+// CHECK-SYMBOLS-DAG: _Z10strongFuncv
+// CHECK-SYMBOLS-DAG: _Z8weakFuncv
+__attribute__((weak)) void weakFunc() {}
+int strongFunc() { return 42; }