Use CheckedNumeric for strength calculation.

core/fxge/ge/cfx_facecache.cpp

 // Copyright 2016 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "core/fxge/include/cfx_facecache.h"
 
 #include <algorithm>
 
@@ skipping 136 matching lines @@
   int weight = 0;
   if (bUseCJKSubFont)
     weight = pSubstFont->m_WeightCJK;
   else
     weight = pSubstFont ? pSubstFont->m_Weight : 0;
   if (pSubstFont && !(pSubstFont->m_SubstFlags & FXFONT_SUBST_MM) &&
       weight > 400) {
     uint32_t index = (weight - 400) / 10;
     if (index >= CFX_Font::kWeightPowArraySize)
       return nullptr;
-    int level = 0;
+    FT_Pos level = 0;

[Wei Li, 2016/08/31 16:59:37]

This may not work on some platform such as Windows, where 'signed long' is still
4 bytes.

[dsinclair, 2016/08/31 18:19:41]

Switched to CheckedNumeric.

     if (pSubstFont->m_Charset == FXFONT_SHIFTJIS_CHARSET) {
-      level =
-          CFX_Font::s_WeightPow_SHIFTJIS[index] * 2 *
-          (FXSYS_abs((int)(ft_matrix.xx)) + FXSYS_abs((int)(ft_matrix.xy))) /
-          36655;
+      level = CFX_Font::s_WeightPow_SHIFTJIS[index] * 2 *
+              static_cast<FT_Pos>(FXSYS_abs(static_cast<int>(ft_matrix.xx)) +
+                                  FXSYS_abs(static_cast<int>(ft_matrix.xy))) /
+              36655;
     } else {
-      level =
-          CFX_Font::s_WeightPow_11[index] *
-          (FXSYS_abs((int)(ft_matrix.xx)) + FXSYS_abs((int)(ft_matrix.xy))) /
-          36655;
+      level = CFX_Font::s_WeightPow_11[index] *
+              static_cast<FT_Pos>(FXSYS_abs(static_cast<int>(ft_matrix.xx)) +

[Lei Zhang, 2016/08/31 17:34:27]

BTW, can we combine the similar portions of the if/else blocks?

[dsinclair, 2016/08/31 18:19:41]

Done.

+                                  FXSYS_abs(static_cast<int>(ft_matrix.xy))) /
+              36655;
     }
     FXFT_Outline_Embolden(FXFT_Get_Glyph_Outline(m_Face), level);
   }
   FXFT_Library_SetLcdFilter(CFX_GEModule::Get()->GetFontMgr()->GetFTLibrary(),
                             FT_LCD_FILTER_DEFAULT);
   error = FXFT_Render_Glyph(m_Face, anti_alias);
   if (error)
     return nullptr;
   int bmwidth = FXFT_Get_Bitmap_Width(FXFT_Get_Glyph_Bitmap(m_Face));
   int bmheight = FXFT_Get_Bitmap_Rows(FXFT_Get_Glyph_Bitmap(m_Face));
@@ skipping 197 matching lines @@
     return it2->second;
 
   CFX_GlyphBitmap* pGlyphBitmap = RenderGlyph(pFont, glyph_index, bFontStyle,
                                               pMatrix, dest_width, anti_alias);
   if (!pGlyphBitmap)
     return nullptr;
 
   pSizeCache->m_GlyphMap[glyph_index] = pGlyphBitmap;
   return pGlyphBitmap;
 }