From: Benjamin Kramer <benny.kra@googlemail.com>
Date: Tue, 4 Aug 2015 13:34:50 +0000 (+0000)
Subject: [AST] Really allocate a SmallVector to the right size.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=6bcb1609b940850f3b1ce660c9026ab7e0804bcf;p=clang

[AST] Really allocate a SmallVector to the right size.

set_size only resets the end pointer and asserts if it is used to grow
the buffer. This would crash when mangling a float with more than 80 bits,
add a test with a ppc double double (128 bits).

Found by inspection.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@243979 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/AST/ItaniumMangle.cpp b/lib/AST/ItaniumMangle.cpp
index dac803e5d2..e51aad9ad8 100644
--- a/lib/AST/ItaniumMangle.cpp
+++ b/lib/AST/ItaniumMangle.cpp
@@ -700,8 +700,7 @@ void CXXNameMangler::mangleFloat(const llvm::APFloat &f) {
   assert(numCharacters != 0);
 
   // Allocate a buffer of the right number of characters.
-  SmallVector<char, 20> buffer;
-  buffer.set_size(numCharacters);
+  SmallVector<char, 20> buffer(numCharacters);
 
   // Fill the buffer left-to-right.
   for (unsigned stringIndex = 0; stringIndex != numCharacters; ++stringIndex) {
diff --git a/test/CodeGenCXX/mangle-literal-suffix.cpp b/test/CodeGenCXX/mangle-literal-suffix.cpp
index ab557d5a1b..d3ca9ffc37 100644
--- a/test/CodeGenCXX/mangle-literal-suffix.cpp
+++ b/test/CodeGenCXX/mangle-literal-suffix.cpp
@@ -1,4 +1,5 @@
-// RUN: %clang_cc1 -triple mips-none-none -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -triple mips-none-none -emit-llvm -o - %s | FileCheck %s -check-prefix=CHECK -check-prefix=FP64
+// RUN: %clang_cc1 -triple powerpc64-none-none -emit-llvm -o - %s | FileCheck %s -check-prefix=CHECK -check-prefix=FP128
 
 template <class T> void g3(char (&buffer)[sizeof(T() + 5.0)]) {}
 template void g3<int>(char (&)[sizeof(double)]);
@@ -6,7 +7,8 @@ template void g3<int>(char (&)[sizeof(double)]);
 
 template <class T> void g4(char (&buffer)[sizeof(T() + 5.0L)]) {}
 template void g4<int>(char (&)[sizeof(long double)]);
-// CHECK: _Z2g4IiEvRAszplcvT__ELe4014000000000000E_c
+// FP64: _Z2g4IiEvRAszplcvT__ELe4014000000000000E_c
+// FP128: _Z2g4IiEvRAszplcvT__ELg00000000000000004014000000000000E_c
 
 template <class T> void g5(char (&buffer)[sizeof(T() + 5)]) {}
 template void g5<int>(char (&)[sizeof(int)]);