Force compiler to deduce src type for checked_cast<dst, src>.

Otherwise, we might be silently doing an unsafe cast before
applying the check if the actual argument doesn't match the
exact src type.

Review-Url: https://codereview.chromium.org/2484953003

2 files changed, 3 insertions, 5 deletions

diff --git a/core/fpdfapi/parser/cpdf_parser.cpp b/core/fpdfapi/parser/cpdf_parser.cpp
index cf23ec7cd7..ed20cf73f4 100644
--- a/core/fpdfapi/parser/cpdf_parser.cpp
+++ b/core/fpdfapi/parser/cpdf_parser.cpp
@@ -1015,10 +1015,8 @@ bool CPDF_Parser::LoadCrossRefV5(FX_FILESIZE* pos, bool bMainXRef) {
     if (startnum < 0)
       continue;
 
-    m_dwXrefStartObjNum =
-        pdfium::base::checked_cast<uint32_t, int32_t>(startnum);
-    uint32_t count =
-        pdfium::base::checked_cast<uint32_t, int32_t>(arrIndex[i].second);
+    m_dwXrefStartObjNum = pdfium::base::checked_cast<uint32_t>(startnum);
+    uint32_t count = pdfium::base::checked_cast<uint32_t>(arrIndex[i].second);
     FX_SAFE_UINT32 dwCaculatedSize = segindex;
     dwCaculatedSize += count;
     dwCaculatedSize *= totalWidth;
diff --git a/core/fpdfdoc/cpdf_formfield.cpp b/core/fpdfdoc/cpdf_formfield.cpp
index e2240c9f2f..8170b7fcbf 100644
--- a/core/fpdfdoc/cpdf_formfield.cpp
+++ b/core/fpdfdoc/cpdf_formfield.cpp
@@ -682,7 +682,7 @@ int CPDF_FormField::InsertOption(CFX_WideString csOptLabel,
     m_pDict->SetFor("Opt", pOpt);
   }
 
-  int iCount = pdfium::base::checked_cast<int, size_t>(pOpt->GetCount());
+  int iCount = pdfium::base::checked_cast<int>(pOpt->GetCount());
   if (index >= iCount) {
     pOpt->AddString(csStr);
     index = iCount;