diff options
| -rw-r--r-- | lib/Analysis/Lint.cpp | 18 | ||||
| -rw-r--r-- | test/Other/lint.ll | 5 |
2 files changed, 16 insertions, 7 deletions
diff --git a/lib/Analysis/Lint.cpp b/lib/Analysis/Lint.cpp index 9258aeee55..7bd945733b 100644 --- a/lib/Analysis/Lint.cpp +++ b/lib/Analysis/Lint.cpp @@ -430,13 +430,17 @@ void Lint::visitMemoryReference(Instruction &I, BaseAlign = AI->getAlignment(); if (BaseAlign == 0 && ATy->isSized()) BaseAlign = TD->getABITypeAlignment(ATy); - } else if (GlobalValue *GV = dyn_cast<GlobalVariable>(Base)) { - Type *GTy = GV->getType()->getElementType(); - if (GTy->isSized()) - BaseSize = TD->getTypeAllocSize(GTy); - BaseAlign = GV->getAlignment(); - if (BaseAlign == 0 && GTy->isSized()) - BaseAlign = TD->getABITypeAlignment(GTy); + } else if (GlobalVariable *GV = dyn_cast<GlobalVariable>(Base)) { + // If the global may be defined differently in another compilation unit + // then don't warn about funky memory accesses. + if (GV->hasDefinitiveInitializer()) { + Type *GTy = GV->getType()->getElementType(); + if (GTy->isSized()) + BaseSize = TD->getTypeAllocSize(GTy); + BaseAlign = GV->getAlignment(); + if (BaseAlign == 0 && GTy->isSized()) + BaseAlign = TD->getABITypeAlignment(GTy); + } } // Accesses from before the start or after the end of the object are not diff --git a/test/Other/lint.ll b/test/Other/lint.ll index d3ab98872d..78bbbe9e6f 100644 --- a/test/Other/lint.ll +++ b/test/Other/lint.ll @@ -9,6 +9,7 @@ declare void @has_noaliases(i32* noalias %p, i32* %q) declare void @one_arg(i32) @CG = constant i32 7 +@E = external global i8 define i32 @foo() noreturn { %buf = alloca i8 @@ -100,6 +101,10 @@ next: ret i32 0 foo: +; CHECK-NOT: Undefined behavior: Buffer overflow +; CHECK-NOT: Memory reference address is misaligned + %e = bitcast i8* @E to i64* + store i64 0, i64* %e %z = add i32 0, 0 ; CHECK: unreachable immediately preceded by instruction without side effects unreachable |