[libclang] visit c++14 lambda capture init expressions

[milianw]

Summary

Previously, libclang users could visit the non-init C++11 lambda
captures, e.g. [foo]. But C++14 init-captures such as [foo=bar]
were skipped, which is fixed by this patch.

[nik]

Tests do not pass on current trunk:

/d2/llvm/trunk/builds/DebugShared % bin/llvm-lit -a /d2/llvm/trunk/source/tools/clang/test/Index/cxx14-lambdas.cpp
llvm-lit: /d2/llvm/trunk/source/utils/lit/lit/llvm/config.py:341: note: using clang: /d2/llvm/trunk/builds/DebugShared/bin/clang
-- Testing: 1 tests, single process --
FAIL: Clang :: Index/cxx14-lambdas.cpp (1 of 1)
******************** TEST 'Clang :: Index/cxx14-lambdas.cpp' FAILED ********************
Script:
--
: 'RUN: at line 13';   /d2/llvm/trunk/builds/DebugShared/bin/c-index-test -test-load-source all -std=c++14 /d2/llvm/trunk/source/tools/clang/test/Index/cxx14-lambdas.cpp | /d2/llvm/trunk/builds/DebugShared/bin/FileCheck -check-prefix=CHECK-LOAD /d2/llvm/trunk/source/tools/clang/test/Index/cxx14-lambdas.cpp
: 'RUN: at line 30';   env CINDEXTEST_INDEXLOCALSYMBOLS=1 /d2/llvm/trunk/builds/DebugShared/bin/c-index-test -index-file -std=c++14 /d2/llvm/trunk/source/tools/clang/test/Index/cxx14-lambdas.cpp | /d2/llvm/trunk/builds/DebugShared/bin/FileCheck -check-prefix=CHECK-INDEX /d2/llvm/trunk/source/tools/clang/test/Index/cxx14-lambdas.cpp
--
Exit Code: 1

Command Output (stderr):
--
/d2/llvm/trunk/source/tools/clang/test/Index/cxx14-lambdas.cpp:22:16: error: CHECK-LOAD: expected string not found in input
// CHECK-LOAD: cxx14-lambdas.cpp:7:27: DeclRefExpr=localA:6:9 Extent=[7:27 - 7:33]
               ^
<stdin>:390:1: note: scanning from here
// CHECK: cxx14-lambdas.cpp:7:59: ParmDecl=x:7:59 (Definition) Extent=[7:51 - 7:60]
^
<stdin>:402:11: note: possible intended match here
// CHECK: cxx14-lambdas.cpp:8:21: DeclRefExpr=copy:7:35 Extent=[8:21 - 8:25]
          ^

--

********************
Testing Time: 0.13s
********************
Failing Tests (1):
    Clang :: Index/cxx14-lambdas.cpp

  Unexpected Failures: 1
zsh: exit 1     bin/llvm-lit -a /d2/llvm/trunk/source/tools/clang/test/Index/cxx14-lambdas.cp

[milianw]

@nik odd, it works for me, I just switched to master (previously I used the 8x release branch) and applied this patch and build it all. Then I run:

$ make && ./bin/llvm-lit ~/projects/src/llvm-project/clang/test/Index/cxx14-lambdas.cpp
makeobj[0]: Entering directory `/home/milian/projects/build/llvm-project'
ninja: no work to do.
makeobj[0]: Leaving directory `/home/milian/projects/build/llvm-project'
llvm-lit: /home/milian/projects/src/llvm-project/llvm/utils/lit/lit/llvm/config.py:340: note: using clang: /home/milian/projects/build/llvm-project/bin/clang
-- Testing: 1 tests, single process --
PASS: Clang :: Index/cxx14-lambdas.cpp (1 of 1)
Testing Time: 0.09s
  Expected Passes    : 1

Are you sure you have compiled this patch? If I comment out the visit of the InitExpr in CIndex.cpp again, then I get the same failure as you:

$ make && ./bin/llvm-lit -a ~/projects/src/llvm-project/clang/test/Index/cxx14-lambdas.cpp
makeobj[0]: Entering directory `/home/milian/projects/build/llvm-project'
ninja: no work to do.
makeobj[0]: Leaving directory `/home/milian/projects/build/llvm-project'
llvm-lit: /home/milian/projects/src/llvm-project/llvm/utils/lit/lit/llvm/config.py:340: note: using clang: /home/milian/projects/build/llvm-project/bin/clang
-- Testing: 1 tests, single process --
FAIL: Clang :: Index/cxx14-lambdas.cpp (1 of 1)
******************** TEST 'Clang :: Index/cxx14-lambdas.cpp' FAILED ********************
Script:
--
: 'RUN: at line 13';   /home/milian/projects/build/llvm-project/bin/c-index-test -test-load-source all -std=c++14 /home/milian/projects/src/llvm-project/clang/test/Index/cxx14-lambdas.cpp | /home/milian/projects/build/llvm-project/bin/FileCheck -check-prefix=CHECK-LOAD /home/milian/projects/src/llvm-project/clang/test/Index/cxx14-lambdas.cpp
: 'RUN: at line 30';   env CINDEXTEST_INDEXLOCALSYMBOLS=1 /home/milian/projects/build/llvm-project/bin/c-index-test -index-file -std=c++14 /home/milian/projects/src/llvm-project/clang/test/Index/cxx14-lambdas.cpp | /home/milian/projects/build/llvm-project/bin/FileCheck -check-prefix=CHECK-INDEX /home/milian/projects/src/llvm-project/clang/test/Index/cxx14-lambdas.cpp
--
Exit Code: 1

Command Output (stderr):
--
/home/milian/projects/src/llvm-project/clang/test/Index/cxx14-lambdas.cpp:22:16: error: CHECK-LOAD: expected string not found in input
// CHECK-LOAD: cxx14-lambdas.cpp:7:27: DeclRefExpr=localA:6:9 Extent=[7:27 - 7:33]
               ^
<stdin>:390:1: note: scanning from here
// CHECK: cxx14-lambdas.cpp:7:59: ParmDecl=x:7:59 (Definition) Extent=[7:51 - 7:60]
^
<stdin>:402:11: note: possible intended match here
// CHECK: cxx14-lambdas.cpp:8:21: DeclRefExpr=copy:7:35 Extent=[8:21 - 8:25]
          ^

--

********************
Testing Time: 0.07s
********************
Failing Tests (1):
    Clang :: Index/cxx14-lambdas.cpp

  Unexpected Failures: 1

Re-enabling the code and building again, it works fine again:

$ make && ./bin/llvm-lit -a ~/projects/src/llvm-project/clang/test/Index/cxx14-lambdas.cpp
makeobj[0]: Entering directory `/home/milian/projects/build/llvm-project'
[5/5] Linking CXX executable bin/c-index-test
makeobj[0]: Leaving directory `/home/milian/projects/build/llvm-project'
llvm-lit: /home/milian/projects/src/llvm-project/llvm/utils/lit/lit/llvm/config.py:340: note: using clang: /home/milian/projects/build/llvm-project/bin/clang
-- Testing: 1 tests, single process --
PASS: Clang :: Index/cxx14-lambdas.cpp (1 of 1)
Script:
--
: 'RUN: at line 13';   /home/milian/projects/build/llvm-project/bin/c-index-test -test-load-source all -std=c++14 /home/milian/projects/src/llvm-project/clang/test/Index/cxx14-lambdas.cpp | /home/milian/projects/build/llvm-project/bin/FileCheck -check-prefix=CHECK-LOAD /home/milian/projects/src/llvm-project/clang/test/Index/cxx14-lambdas.cpp
: 'RUN: at line 30';   env CINDEXTEST_INDEXLOCALSYMBOLS=1 /home/milian/projects/build/llvm-project/bin/c-index-test -index-file -std=c++14 /home/milian/projects/src/llvm-project/clang/test/Index/cxx14-lambdas.cpp | /home/milian/projects/build/llvm-project/bin/FileCheck -check-prefix=CHECK-INDEX /home/milian/projects/src/llvm-project/clang/test/Index/cxx14-lambdas.cpp
--
Exit Code: 0


********************
Testing Time: 0.14s
  Expected Passes    : 1

[nik]

Are you sure you have compiled this patch? If I comment out the visit of the InitExpr in CIndex.cpp again, then I get the same failure as you...

Huch, I've indeed somehow missed to compile. Sorry for that. Works fine after compilation :)

LGTM.

[milianw]

Do you have commit rights? Can you push that for me?

[milianw]

thanks!

test/Index/cxx14-lambdas.cpp

+// Test is line- and column-sensitive; see below.
+
+typedef int Integer;
+struct X {
+  void f() {
+    int localA, localB;
+    auto lambda = [ptr = &localA, copy = localB] (Integer x) -> Integer {
+      return *ptr + copy + x;
+    };
+  }
+};
+
+// RUN: c-index-test -test-load-source all -std=c++14 %s | FileCheck -check-prefix=CHECK-LOAD %s
+// CHECK-LOAD: cxx14-lambdas.cpp:7:5: DeclStmt= Extent=[7:5 - 9:7]
+// CHECK-LOAD: cxx14-lambdas.cpp:7:10: VarDecl=lambda:7:10 (Definition) Extent=[7:5 - 9:6]
+// CHECK-LOAD: cxx14-lambdas.cpp:7:19: UnexposedExpr= Extent=[7:19 - 9:6]
+// CHECK-LOAD: cxx14-lambdas.cpp:7:19: CallExpr= Extent=[7:19 - 9:6]
+// CHECK-LOAD: cxx14-lambdas.cpp:7:19: UnexposedExpr= Extent=[7:19 - 9:6]
+// CHECK-LOAD: cxx14-lambdas.cpp:7:19: LambdaExpr= Extent=[7:19 - 9:6]
+// CHECK-LOAD: cxx14-lambdas.cpp:7:20: VariableRef=ptr:7:20 Extent=[7:20 - 7:23]
+// CHECK-LOAD: cxx14-lambdas.cpp:7:35: VariableRef=copy:7:35 Extent=[7:35 - 7:39]
+// CHECK-LOAD: cxx14-lambdas.cpp:7:27: DeclRefExpr=localA:6:9 Extent=[7:27 - 7:33]
+// CHECK-LOAD: cxx14-lambdas.cpp:7:42: DeclRefExpr=localB:6:17 Extent=[7:42 - 7:48]
+// CHECK-LOAD: cxx14-lambdas.cpp:7:59: ParmDecl=x:7:59 (Definition) Extent=[7:51 - 7:60]
+// CHECK-LOAD: cxx14-lambdas.cpp:7:51: TypeRef=Integer:3:13 Extent=[7:51 - 7:58]
+// CHECK-LOAD: cxx14-lambdas.cpp:7:65: TypeRef=Integer:3:13 Extent=[7:65 - 7:72]
+// CHECK-LOAD: cxx14-lambdas.cpp:7:73: CompoundStmt= Extent=[7:73 - 9:6]
+// CHECK-LOAD: cxx14-lambdas.cpp:8:7: ReturnStmt= Extent=[8:7 - 8:29]
+
+// RUN: env CINDEXTEST_INDEXLOCALSYMBOLS=1 c-index-test -index-file -std=c++14 %s | FileCheck -check-prefix=CHECK-INDEX %s
+// CHECK-INDEX: [indexEntityReference]: kind: variable | name: ptr | USR: c:cxx14-lambdas.cpp@139@S@X@F@f#@Sa@F@operator()#I#1@ptr | lang: C | cursor: VariableRef=ptr:7:20 | loc: 7:20
+// CHECK-INDEX: [indexEntityReference]: kind: variable | name: copy | USR: c:cxx14-lambdas.cpp@154@S@X@F@f#@Sa@F@operator()#I#1@copy | lang: C | cursor: VariableRef=copy:7:35 | loc: 7:35
+// CHECK-INDEX: [indexDeclaration]: kind: variable | name: x | USR: c:cxx14-lambdas.cpp@170@S@X@F@f#@Sa@F@operator()#I#1@x | lang: C | cursor: ParmDecl=x:7:59 (Definition) | loc: 7:59
+// CHECK-INDEX: [indexEntityReference]: kind: typedef | name: Integer | USR: c:cxx14-lambdas.cpp@T@Integer | lang: C | cursor: TypeRef=Integer:3:13 | loc: 7:51
+// CHECK-INDEX: [indexEntityReference]: kind: typedef | name: Integer | USR: c:cxx14-lambdas.cpp@T@Integer | lang: C | cursor: TypeRef=Integer:3:13 | loc: 7:65
+// CHECK-INDEX: [indexEntityReference]: kind: variable | name: ptr | USR: c:cxx14-lambdas.cpp@139@S@X@F@f#@Sa@F@operator()#I#1@ptr | lang: C | cursor: DeclRefExpr=ptr:7:20 | loc: 8:15
+// CHECK-INDEX: [indexEntityReference]: kind: variable | name: copy | USR: c:cxx14-lambdas.cpp@154@S@X@F@f#@Sa@F@operator()#I#1@copy | lang: C | cursor: DeclRefExpr=copy:7:35 | loc: 8:21
+// CHECK-INDEX: [indexEntityReference]: kind: variable | name: x | USR: c:cxx14-lambdas.cpp@170@S@X@F@f#@Sa@F@operator()#I#1@x | lang: C | cursor: DeclRefExpr=x:7:59 | loc: 8:28

tools/libclang/CIndex.cpp

switch (LI.getKind()) {
         }
         
         // Non-type template parameter packs and function parameter packs are
         // treated like DeclRefExpr cursors.
         continue;
       }
         
       case VisitorJob::LambdaExprPartsKind: {
-        // Visit captures.
+        // Visit non-init captures.
         const LambdaExpr *E = cast<LambdaExprParts>(&LI)->get();
         for (LambdaExpr::capture_iterator C = E->explicit_capture_begin(),
                                        CEnd = E->explicit_capture_end();
              C != CEnd; ++C) {
-          // FIXME: Lambda init-captures.
           if (!C->capturesVariable())
             continue;
 
           if (Visit(MakeCursorVariableRef(C->getCapturedVar(),
                                           C->getLocation(),
                                           TU)))
             return true;
         }
+        // Visit init captures
+        for (auto InitExpr : E->capture_inits()) {
+          if (Visit(InitExpr))
+            return true;
+        }
         
         TypeLoc TL = E->getCallOperator()->getTypeSourceInfo()->getTypeLoc();
         // Visit parameters and return type, if present.
         if (FunctionTypeLoc Proto = TL.getAs<FunctionProtoTypeLoc>()) {
           if (E->hasExplicitParameters()) {
             // Visit parameters.
             for (unsigned I = 0, N = Proto.getNumParams(); I != N; ++I)
               if (Visit(MakeCXCursor(Proto.getParam(I), TU)))