[scudo] Fix CHECK implementation

[vitalybuka]

Summary

Cast of signed types to u64 breaks comparison.
Also remove double () around operands.

[cryptoad]

Right, that makes sense, thank you Vitaly!
FWIW, this was originally taken from CHECK_IMPL in sanitizer_common that seems to display the same behavior: https://github.com/llvm/llvm-project/blob/main/compiler-rt/lib/sanitizer_common/sanitizer_internal_defs.h#L289

[hctim]

LGTM

compiler-rt/lib/scudo/standalone/internal_defs.h

if (UNLIKELY(!(Expr))) {                                                   \
       die();                                                                   \
     }                                                                          \
   } while (false)
 
 #define RAW_CHECK(Expr) RAW_CHECK_MSG(Expr, #Expr)
 
 void NORETURN reportCheckFailed(const char *File, int Line,
                                 const char *Condition, u64 Value1, u64 Value2);
-
 #define CHECK_IMPL(C1, Op, C2)                                                 \
   do {                                                                         \
-    scudo::u64 V1 = (scudo::u64)(C1);                                          \
-    scudo::u64 V2 = (scudo::u64)(C2);                                          \
-    if (UNLIKELY(!(V1 Op V2))) {                                               \
-      scudo::reportCheckFailed(__FILE__, __LINE__,                             \
-                               "(" #C1 ") " #Op " (" #C2 ")", V1, V2);         \
+    if (UNLIKELY(!(C1 Op C2))) {                                               \
+      scudo::reportCheckFailed(__FILE__, __LINE__, #C1 " " #Op " " #C2,        \
+                               (scudo::u64)C1, (scudo::u64)C2);                \
       scudo::die();                                                            \
     }                                                                          \
   } while (false)
 
 #define CHECK(A) CHECK_IMPL((A), !=, 0)
 #define CHECK_EQ(A, B) CHECK_IMPL((A), ==, (B))
 #define CHECK_NE(A, B) CHECK_IMPL((A), !=, (B))
 #define CHECK_LT(A, B) CHECK_IMPL((A), <, (B))

compiler-rt/lib/scudo/standalone/report.cpp

 void NORETURN reportCheckFailed(const char *File, int Line,
                                 const char *Condition, u64 Value1, u64 Value2) {
   static atomic_u32 NumberOfCalls;
   if (atomic_fetch_add(&NumberOfCalls, 1, memory_order_relaxed) > 2) {
     // TODO(kostyak): maybe sleep here?
     trap();
   }
   ScopedErrorReport Report;
-  Report.append("CHECK failed @ %s:%d %s (%llu, %llu)\n", File, Line, Condition,
-                Value1, Value2);
+  Report.append("CHECK failed @ %s:%d %s ((u64)op1=%llu, (u64)op2=%llu)\n",
+                File, Line, Condition, Value1, Value2);
 }
 
 // Generic string fatal error message.
 void NORETURN reportError(const char *Message) {
   ScopedErrorReport Report;
   Report.append("%s\n", Message);
 }
 

compiler-rt/lib/scudo/standalone/tests/report_test.cpp

 //===-- report_test.cpp -----------------------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 #include "tests/scudo_unit_test.h"
 
 #include "report.h"
 
+TEST(ScudoReportTest, Check) {
+  CHECK_LT(-1, 1);
+  EXPECT_DEATH(CHECK_GT(-1, 1),
+               "\\(-1\\) > \\(1\\) \\(\\(u64\\)op1=18446744073709551615, "
+               "\\(u64\\)op2=1");
+}
+
 TEST(ScudoReportTest, Generic) {
   // Potentially unused if EXPECT_DEATH isn't defined.
   UNUSED void *P = reinterpret_cast<void *>(0x42424242U);
   EXPECT_DEATH(scudo::reportError("TEST123"), "Scudo ERROR.*TEST123");
   EXPECT_DEATH(scudo::reportInvalidFlag("ABC", "DEF"), "Scudo ERROR.*ABC.*DEF");
   EXPECT_DEATH(scudo::reportHeaderCorruption(P), "Scudo ERROR.*42424242");
   EXPECT_DEATH(scudo::reportHeaderRace(P), "Scudo ERROR.*42424242");
   EXPECT_DEATH(scudo::reportSanityCheckError("XYZ"), "Scudo ERROR.*XYZ");