Clean up use of C allocation functions

If the value returned by `malloc`, `calloc` or `realloc` is not checked
for null pointer, this change replaces them for `safe_malloc`,
`safe_calloc` or `safe_realloc`, which are defined in the namespace `llvm`.
These function report fatal error on out of memory.

In the plain C files, assertion statements are added to ensure that memory
is successfully allocated.

The aim of this change is to get better diagnostics of OOM on Windows.

Differential Revision: https://reviews.llvm.org/D43017

llvm-svn: 325661

4 files changed, 8 insertions, 7 deletions

diff --git a/clang/lib/AST/NestedNameSpecifier.cpp b/clang/lib/AST/NestedNameSpecifier.cpp
index 889f8308a93..f46552e337e 100644
--- a/clang/lib/AST/NestedNameSpecifier.cpp
+++ b/clang/lib/AST/NestedNameSpecifier.cpp
@@ -466,7 +466,7 @@ static void Append(char *Start, char *End, char *&Buffer, unsigned &BufferSize,
     unsigned NewCapacity = std::max(
         (unsigned)(BufferCapacity ? BufferCapacity * 2 : sizeof(void *) * 2),
         (unsigned)(BufferSize + (End - Start)));
-    char *NewBuffer = static_cast<char *>(malloc(NewCapacity));
+    char *NewBuffer = static_cast<char *>(llvm::safe_malloc(NewCapacity));
     if (BufferCapacity) {
       memcpy(NewBuffer, Buffer, BufferSize);
       free(Buffer);
diff --git a/clang/lib/Frontend/CacheTokens.cpp b/clang/lib/Frontend/CacheTokens.cpp
index 72e8f68dc05..851ea25e9b1 100644
--- a/clang/lib/Frontend/CacheTokens.cpp
+++ b/clang/lib/Frontend/CacheTokens.cpp
@@ -662,7 +662,8 @@ std::pair<Offset,Offset> PTHWriter::EmitIdentifierTable() {
   //  (2) a map from (IdentifierInfo*, Offset)* -> persistent IDs
 
   // Note that we use 'calloc', so all the bytes are 0.
-  PTHIdKey *IIDMap = (PTHIdKey*)calloc(idcount, sizeof(PTHIdKey));
+  PTHIdKey *IIDMap = static_cast<PTHIdKey*>(
+      llvm::safe_calloc(idcount, sizeof(PTHIdKey)));
 
   // Create the hashtable.
   llvm::OnDiskChainedHashTableGenerator<PTHIdentifierTableTrait> IIOffMap;
diff --git a/clang/lib/Frontend/Rewrite/HTMLPrint.cpp b/clang/lib/Frontend/Rewrite/HTMLPrint.cpp
index 11e431de0a3..34ee9673cc5 100644
--- a/clang/lib/Frontend/Rewrite/HTMLPrint.cpp
+++ b/clang/lib/Frontend/Rewrite/HTMLPrint.cpp
@@ -86,8 +86,7 @@ void HTMLPrinter::HandleTranslationUnit(ASTContext &Ctx) {
 
   // Emit the HTML.
   const RewriteBuffer &RewriteBuf = R.getEditBuffer(FID);
-  char *Buffer = (char*)malloc(RewriteBuf.size());
-  std::copy(RewriteBuf.begin(), RewriteBuf.end(), Buffer);
-  Out->write(Buffer, RewriteBuf.size());
-  free(Buffer);
+  std::unique_ptr<char[]> Buffer(new char[RewriteBuf.size()]);
+  std::copy(RewriteBuf.begin(), RewriteBuf.end(), Buffer.get());
+  Out->write(Buffer.get(), RewriteBuf.size());
 }
diff --git a/clang/lib/Lex/MacroArgs.cpp b/clang/lib/Lex/MacroArgs.cpp
index 5c0f0623c3e..df3f8a4877a 100644
--- a/clang/lib/Lex/MacroArgs.cpp
+++ b/clang/lib/Lex/MacroArgs.cpp
@@ -49,7 +49,8 @@ MacroArgs *MacroArgs::create(const MacroInfo *MI,
   if (!ResultEnt) {
     // Allocate memory for a MacroArgs object with the lexer tokens at the end,
     // and construct the MacroArgs object.
-    Result = new (std::malloc(totalSizeToAlloc<Token>(UnexpArgTokens.size())))
+    Result = new (
+        llvm::safe_malloc(totalSizeToAlloc<Token>(UnexpArgTokens.size())))
         MacroArgs(UnexpArgTokens.size(), VarargsElided, MI->getNumParams());
   } else {
     Result = *ResultEnt;