[compiler-rt] r207415 - [asan] split detect_odr_violation into two: =2 detects all ODR violations, =1 detects only those where the variable sizes are different. BTW, the detector seems to be working well and finding nice bugs. Early adopters are welcome.

[Kostya Serebryany]

Author: kcc
Date: Mon Apr 28 07:47:58 2014
New Revision: 207415

URL: http://llvm.org/viewvc/llvm-project?rev=207415&view=rev
Log:
[asan] split detect_odr_violation into two: =2 detects all ODR violations, =1 detects only those where the variable sizes are different. BTW, the detector seems to be working well and finding nice bugs. Early adopters are welcome.

Modified:
    compiler-rt/trunk/lib/asan/asan_flags.h
    compiler-rt/trunk/lib/asan/asan_globals.cc
    compiler-rt/trunk/lib/asan/asan_rtl.cc
    compiler-rt/trunk/test/asan/TestCases/Linux/odr-violation.cc

Modified: compiler-rt/trunk/lib/asan/asan_flags.h
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_flags.h?rev=207415&r1=207414&r2=207415&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_flags.h (original)
+++ compiler-rt/trunk/lib/asan/asan_flags.h Mon Apr 28 07:47:58 2014
@@ -64,7 +64,7 @@ struct Flags {
   bool start_deactivated;
   int detect_invalid_pointer_pairs;
   bool detect_container_overflow;
-  bool detect_odr_violation;
+  int detect_odr_violation;
 };
 
 extern Flags asan_flags_dont_use_directly;

Modified: compiler-rt/trunk/lib/asan/asan_globals.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_globals.cc?rev=207415&r1=207414&r2=207415&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_globals.cc (original)
+++ compiler-rt/trunk/lib/asan/asan_globals.cc Mon Apr 28 07:47:58 2014
@@ -99,7 +99,8 @@ static void RegisterGlobal(const Global
       // This check may not be enough: if the first global is much larger
       // the entire redzone of the second global may be within the first global.
       for (ListOfGlobals *l = list_of_all_globals; l; l = l->next) {
-        if (g->beg == l->g->beg)
+        if (g->beg == l->g->beg &&
+            (flags()->detect_odr_violation >= 2 || g->size != l->g->size))
           ReportODRViolation(g, l->g);
       }
     }

Modified: compiler-rt/trunk/lib/asan/asan_rtl.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/asan/asan_rtl.cc?rev=207415&r1=207414&r2=207415&view=diff
==============================================================================
--- compiler-rt/trunk/lib/asan/asan_rtl.cc (original)
+++ compiler-rt/trunk/lib/asan/asan_rtl.cc Mon Apr 28 07:47:58 2014
@@ -226,9 +226,10 @@ static void ParseFlagsFromString(Flags *
       "If true, honor the container overflow  annotations. "
       "See https://code.google.com/p/address-sanitizer/wiki/ContainerOverflow");
 
-  ParseFlag(str, &f->detect_odr_violation,
-      "detect_odr_violation",
-      "If true, detect violation of One-Definition-Rule (ODR) ");
+  ParseFlag(str, &f->detect_odr_violation, "detect_odr_violation",
+            "If >=2, detect violation of One-Definition-Rule (ODR); "
+            "If ==1, detect ODR-violation only if the two variables "
+            "have different sizes");
 }
 
 void InitializeFlags(Flags *f, const char *env) {

Modified: compiler-rt/trunk/test/asan/TestCases/Linux/odr-violation.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/test/asan/TestCases/Linux/odr-violation.cc?rev=207415&r1=207414&r2=207415&view=diff
==============================================================================
--- compiler-rt/trunk/test/asan/TestCases/Linux/odr-violation.cc (original)
+++ compiler-rt/trunk/test/asan/TestCases/Linux/odr-violation.cc Mon Apr 28 07:47:58 2014
@@ -1,8 +1,16 @@
-// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared %s -o %t.so
 // RUN: %clangxx_asan %s %t.so -Wl,-R. -o %t
+//
+// Different size: detect a bug if detect_odr_violation>=1
+// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared %s -o %t.so
 // RUN: ASAN_OPTIONS=detect_odr_violation=1 not %t 2>&1 | FileCheck %s
+// RUN: ASAN_OPTIONS=detect_odr_violation=2 not %t 2>&1 | FileCheck %s
 // RUN: ASAN_OPTIONS=detect_odr_violation=0     %t 2>&1 | FileCheck %s --check-prefix=DISABLED
 // RUN:                                         %t 2>&1 | FileCheck %s --check-prefix=DISABLED
+//
+// Same size: report a bug only if detect_odr_violation>=2.
+// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared %s -o %t.so -DSZ=100
+// RUN: ASAN_OPTIONS=detect_odr_violation=1     %t 2>&1 | FileCheck %s --check-prefix=DISABLED
+// RUN: ASAN_OPTIONS=detect_odr_violation=2 not %t 2>&1 | FileCheck %s
 
 #ifndef SZ
 # define SZ 4