[analyzer] Fix missed leak from MSVC specific allocation functions

Add the wide character strdup variants (wcsdup, _wcsdup) and the MSVC
version of alloca (_alloca) and other differently named function used
by the Malloc checker.

A patch by Alexander Riccio!

Differential Revision: http://reviews.llvm.org/D17688

llvm-svn: 262894

1 files changed, 76 insertions, 0 deletions

diff --git a/clang/test/Analysis/malloc.c b/clang/test/Analysis/malloc.c
index 881eb38ad84..30d72691956 100644
--- a/clang/test/Analysis/malloc.c
+++ b/clang/test/Analysis/malloc.c
@@ -4,6 +4,21 @@
 
 void clang_analyzer_eval(int);
 
+// Without -fms-compatibility, wchar_t isn't a builtin type. MSVC defines
+// _WCHAR_T_DEFINED if wchar_t is available. Microsoft recommends that you use
+// the builtin type: "Using the typedef version can cause portability
+// problems", but we're ok here because we're not actually running anything.
+// Also of note is this cryptic warning: "The wchar_t type is not supported
+// when you compile C code".
+//
+// See the docs for more:
+// https://msdn.microsoft.com/en-us/library/dh8che7s.aspx
+#if !defined(_WCHAR_T_DEFINED)
+// "Microsoft implements wchar_t as a two-byte unsigned value"
+typedef unsigned short wchar_t;
+#define _WCHAR_T_DEFINED
+#endif // !defined(_WCHAR_T_DEFINED)
+
 typedef __typeof(sizeof(int)) size_t;
 void *malloc(size_t);
 void *alloca(size_t);
@@ -13,9 +28,15 @@ void *realloc(void *ptr, size_t size);
 void *reallocf(void *ptr, size_t size);
 void *calloc(size_t nmemb, size_t size);
 char *strdup(const char *s);
+wchar_t *wcsdup(const wchar_t *s);
 char *strndup(const char *s, size_t n);
 int memcmp(const void *s1, const void *s2, size_t n);
 
+// Windows variants
+char *_strdup(const char *strSource);
+wchar_t *_wcsdup(const wchar_t *strSource);
+void *_alloca(size_t size);
+
 void myfoo(int *p);
 void myfooint(int p);
 char *fooRetPtr();
@@ -55,6 +76,10 @@ void allocaTest() {
   int *p = alloca(sizeof(int));
 } // no warn
 
+void winAllocaTest() {
+  int *p = _alloca(sizeof(int));
+} // no warn
+
 void allocaBuiltinTest() {
   int *p = __builtin_alloca(sizeof(int));
 } // no warn
@@ -210,6 +235,11 @@ void CheckUseZeroAllocatedNoWarn2() {
   int *p = alloca(0); // no warning
 }
 
+void CheckUseZeroWinAllocatedNoWarn2() {
+  int *p = _alloca(0); // no warning
+}
+
+
 void CheckUseZeroAllocatedNoWarn3() {
   int *p = malloc(0);
   int *q = realloc(p, 8); // no warning
@@ -233,6 +263,11 @@ char CheckUseZeroAllocated2() {
   return *p; // expected-warning {{Use of zero-allocated memory}}
 }
 
+char CheckUseZeroWinAllocated2() {
+  char *p = _alloca(0);
+  return *p; // expected-warning {{Use of zero-allocated memory}}
+}
+
 void UseZeroAllocated(int *p) {
   if (p)
     *p = 7; // expected-warning {{Use of zero-allocated memory}}
@@ -1076,6 +1111,21 @@ void testStrdup(const char *s, unsigned validIndex) {
   s2[validIndex + 1] = 'b';
 } // expected-warning {{Potential leak of memory pointed to by}}
 
+void testWinStrdup(const char *s, unsigned validIndex) {
+  char *s2 = _strdup(s);
+  s2[validIndex + 1] = 'b';
+} // expected-warning {{Potential leak of memory pointed to by}}
+
+void testWcsdup(const wchar_t *s, unsigned validIndex) {
+  wchar_t *s2 = wcsdup(s);
+  s2[validIndex + 1] = 'b';
+} // expected-warning {{Potential leak of memory pointed to by}}
+
+void testWinWcsdup(const wchar_t *s, unsigned validIndex) {
+  wchar_t *s2 = _wcsdup(s);
+  s2[validIndex + 1] = 'b';
+} // expected-warning {{Potential leak of memory pointed to by}}
+
 int testStrndup(const char *s, unsigned validIndex, unsigned size) {
   char *s2 = strndup(s, size);
   s2 [validIndex + 1] = 'b';
@@ -1091,6 +1141,24 @@ void testStrdupContentIsDefined(const char *s, unsigned validIndex) {
   free(s2);
 }
 
+void testWinStrdupContentIsDefined(const char *s, unsigned validIndex) {
+  char *s2 = _strdup(s);
+  char result = s2[1];// no warning
+  free(s2);
+}
+
+void testWcsdupContentIsDefined(const wchar_t *s, unsigned validIndex) {
+  wchar_t *s2 = wcsdup(s);
+  wchar_t result = s2[1];// no warning
+  free(s2);
+}
+
+void testWinWcsdupContentIsDefined(const wchar_t *s, unsigned validIndex) {
+  wchar_t *s2 = _wcsdup(s);
+  wchar_t result = s2[1];// no warning
+  free(s2);
+}
+
 // ----------------------------------------------------------------------------
 // Test the system library functions to which the pointer can escape.
 // This tests false positive suppression.
@@ -1444,6 +1512,14 @@ char *testLeakWithinReturn(char *str) {
   return strdup(strdup(str)); // expected-warning{{leak}}
 }
 
+char *testWinLeakWithinReturn(char *str) {
+  return _strdup(_strdup(str)); // expected-warning{{leak}}
+}
+
+wchar_t *testWinWideLeakWithinReturn(wchar_t *str) {
+  return _wcsdup(_wcsdup(str)); // expected-warning{{leak}}
+}
+
 void passConstPtr(const char * ptr);
 
 void testPassConstPointer() {