tdf#140401 check if attribute is a nullptr

Change-Id: Ie6e33fc1dca525553bb4237204666835d335b13f
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/160524
Tested-by: Jenkins
Reviewed-by: Patrick Luby <plubius@libreoffice.org>
diff --git a/vcl/quartz/SystemFontList.cxx b/vcl/quartz/SystemFontList.cxx
index 2bc7544..e068caf 100644
--- a/vcl/quartz/SystemFontList.cxx
+++ b/vcl/quartz/SystemFontList.cxx
@@ -118,7 +118,9 @@ FontAttributes DevFontFromCTFontDescriptor( CTFontDescriptorRef pFD, bool* bFont
    // get the font weight
    double fWeight = 0;
    CFNumberRef pWeightNum = static_cast<CFNumberRef>(CFDictionaryGetValue( pAttrDict, kCTFontWeightTrait ));
    CFNumberGetValue( pWeightNum, kCFNumberDoubleType, &fWeight );
    // tdf#140401 check if attribute is a nullptr
    if( pWeightNum )
        CFNumberGetValue( pWeightNum, kCFNumberDoubleType, &fWeight );
    int nInt = WEIGHT_NORMAL;

    // Special case fixes
@@ -164,7 +166,9 @@ FontAttributes DevFontFromCTFontDescriptor( CTFontDescriptorRef pFD, bool* bFont
    // get the font slant
    double fSlant = 0;
    CFNumberRef pSlantNum = static_cast<CFNumberRef>(CFDictionaryGetValue( pAttrDict, kCTFontSlantTrait ));
    CFNumberGetValue( pSlantNum, kCFNumberDoubleType, &fSlant );
    // tdf#140401 check if attribute is a nullptr
    if( pSlantNum )
        CFNumberGetValue( pSlantNum, kCFNumberDoubleType, &fSlant );
    if( fSlant >= 0.035 )
    {
        rDFA.SetItalic( ITALIC_NORMAL );
@@ -172,7 +176,9 @@ FontAttributes DevFontFromCTFontDescriptor( CTFontDescriptorRef pFD, bool* bFont
    // get width trait
    double fWidth = 0;
    CFNumberRef pWidthNum = static_cast<CFNumberRef>(CFDictionaryGetValue( pAttrDict, kCTFontWidthTrait ));
    CFNumberGetValue( pWidthNum, kCFNumberDoubleType, &fWidth );
    // tdf#140401 check if attribute is a nullptr
    if( pWidthNum )
        CFNumberGetValue( pWidthNum, kCFNumberDoubleType, &fWidth );
    nInt = WIDTH_NORMAL;

    if( fWidth > 0 )