Add test of automatic struct naming with multiple translation units.

Author: mattmccutchen-cci

clang/test/3C/inline_anon_structs.c

@@ -122,6 +122,13 @@ struct {
 //CHECK_ALL:      };
 //CHECK_ALL-NEXT: _Ptr<struct be_struct_1> be _Checked[4] = {((void *)0)};
 
+// The following is explained in second_tu_fn in inline_anon_structs_cross_tu.c.
+struct { int x; } *cross_tu_numbering_test;
+//CHECK_AB:      struct cross_tu_numbering_test_struct_1 { int x; };
+//CHECK_AB-NEXT: _Ptr<struct cross_tu_numbering_test_struct_1> cross_tu_numbering_test = ((void *)0);
+//CHECK_BA:      struct cross_tu_numbering_test_struct_2 { int x; };
+//CHECK_BA-NEXT: _Ptr<struct cross_tu_numbering_test_struct_2> cross_tu_numbering_test = ((void *)0);
+
 /*this code checks inline structs withiin functions*/
 void foo2(int *x) {
   //CHECK: void foo2(_Ptr<int> x) _Checked {

clang/test/3C/inline_anon_structs_cross_tu.c

@@ -0,0 +1,69 @@
+// Regression tests for two bugs seen during the development of
+// https://github.com/correctcomputation/checkedc-clang/pull/657 with multiple
+// translation units: some information about automatically named TagDecls was
+// not propagated across translation units.
+//
+// Our translation units are inline_anon_structs.c and
+// inline_anon_structs_cross_tu.c; the latter `#include`s the former and has
+// some code of its own. So inline_anon_structs.c effectively plays the role of
+// a shared header file, but we just use the .c file instead of moving the code
+// to a .h file and making another .c file that does nothing but `#include` the
+// .h file.
+//
+// We test 3C on both orders of the translation units. Remember that when the
+// same file is rewritten as part of multiple translation units, the last
+// translation unit wins
+// (https://github.com/correctcomputation/checkedc-clang/issues/374#issuecomment-804283984).
+// So the "inline_anon_structs.c, inline_anon_structs_cross_tu.c" order should
+// catch most problems that occur when 3C makes the decisions in one translation
+// unit but does the rewriting in another. We still test the other order for
+// completeness.
+
+// RUN: rm -rf %t*
+
+// Tests of the "inline_anon_structs.c, inline_anon_structs_cross_tu.c" order
+// (called "AB" for short).
+//
+// Note about check prefixes: We currently don't bother with a Cartesian product
+// of {ALL,NOALL} x {AB,BA} because we don't have any tests whose results depend
+// on both variables. We do pass CHECK_NOALL and CHECK_ALL to
+// inline_anon_structs_cross_tu.c for uniformity, even though that file
+// currently doesn't use either.
+//
+// RUN: 3c -base-dir=%S -addcr -alltypes -output-dir=%t.checkedALL_AB %S/inline_anon_structs.c %s --
+// RUN: FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK","CHECK_AB" --input-file %t.checkedALL_AB/inline_anon_structs.c %S/inline_anon_structs.c
+// RUN: FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK","CHECK_AB" --input-file %t.checkedALL_AB/inline_anon_structs_cross_tu.c %s
+// RUN: 3c -base-dir=%S -addcr -output-dir=%t.checkedNOALL_AB %S/inline_anon_structs.c %s --
+// RUN: FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK","CHECK_AB" --input-file %t.checkedNOALL_AB/inline_anon_structs.c %S/inline_anon_structs.c
+// RUN: FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK","CHECK_AB" --input-file %t.checkedNOALL_AB/inline_anon_structs_cross_tu.c %s
+
+// Tests of the "inline_anon_structs_cross_tu.c, inline_anon_structs.c" order
+// (called "BA").
+//
+// RUN: 3c -base-dir=%S -addcr -alltypes -output-dir=%t.checkedALL_BA  %s %S/inline_anon_structs.c --
+// RUN: FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK","CHECK_BA" --input-file %t.checkedALL_BA/inline_anon_structs.c %S/inline_anon_structs.c
+// RUN: FileCheck -match-full-lines -check-prefixes="CHECK_ALL","CHECK","CHECK_BA" --input-file %t.checkedALL_BA/inline_anon_structs_cross_tu.c %s
+// RUN: 3c -base-dir=%S -addcr -output-dir=%t.checkedNOALL_BA %s %S/inline_anon_structs.c --
+// RUN: FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK","CHECK_BA" --input-file %t.checkedNOALL_BA/inline_anon_structs.c %S/inline_anon_structs.c
+// RUN: FileCheck -match-full-lines -check-prefixes="CHECK_NOALL","CHECK","CHECK_BA" --input-file %t.checkedNOALL_BA/inline_anon_structs_cross_tu.c %s
+
+void second_tu_fn(void) {
+  // In the AB order, the global `cross_tu_numbering_test` variable in
+  // inline_anon_structs.c will be seen first and its struct will be named
+  // cross_tu_numbering_test_struct_1, and this struct will be named
+  // cross_tu_numbering_test_struct_2. In the BA order, this code is seen before
+  // the `#include "inline_anon_structs.c"`, so this struct will take the
+  // cross_tu_numbering_test_struct_1 name and the inline_anon_structs.c one
+  // will be cross_tu_numbering_test_struct_2.
+  //
+  // Note that in order to have two different variables with the same name (in
+  // order to produce a collision in struct names), we have to put the variables
+  // in different scopes: in this case, global and function-local.
+  struct { int y; } *cross_tu_numbering_test;
+  //CHECK_AB:      struct cross_tu_numbering_test_struct_2 { int y; };
+  //CHECK_AB-NEXT: _Ptr<struct cross_tu_numbering_test_struct_2> cross_tu_numbering_test = ((void *)0);
+  //CHECK_BA:      struct cross_tu_numbering_test_struct_1 { int y; };
+  //CHECK_BA-NEXT: _Ptr<struct cross_tu_numbering_test_struct_1> cross_tu_numbering_test = ((void *)0);
+}
+
+#include "inline_anon_structs.c"