Javascript-related segfault on imzdl.com

#0  0x0000000000000000 in ?? ()
#1  0x00007ff33d2fde07 in TSymbolTableLevel::~TSymbolTableLevel (this=0x59c4670, __in_chrg=<optimized out>) at src/compiler/SymbolTable.cpp:174
#2  0x00007ff33d2cee43 in pop (this=0x1ae99c0) at src/compiler/SymbolTable.h:270
#3  TCompiler::compile (this=0x1ae98f0, shaderStrings=shaderStrings@entry=0x7fff1c93bcf0, numStrings=numStrings@entry=1, compileOptions=<optimized out>, compileOptions@entry=4172) at src/compiler/Compiler.cpp:204
#4  0x00007ff33d2fd176 in ShCompile (handle=0x1ae98f0, shaderStrings=0x7fff1c93bcf0, numStrings=1, compileOptions=4172) at src/compiler/ShaderLang.cpp:200
#5  0x00007ff33bfec9b3 in WebCore::ANGLEWebKitBridge::compileShaderSource (this=<optimized out>, shaderSource=<optimized out>, shaderType=<optimized out>, translatedShaderSource=..., shaderValidationLog=..., symbols=..., 
    extraCompileOptions=4160) at platform/graphics/ANGLEWebKitBridge.cpp:192
#6  0x00007ff33c003cd7 in WebCore::Extensions3DOpenGLCommon::getTranslatedShaderSourceANGLE (this=0x1040, shader=2) at platform/graphics/opengl/Extensions3DOpenGLCommon.cpp:179
#7  0x00007ff33bffcf39 in WebCore::GraphicsContext3D::compileShader (this=0x19211a0, shader=2) at platform/graphics/opengl/GraphicsContext3DOpenGLCommon.cpp:443
#8  0x00007ff33c455448 in WebCore::jsWebGLRenderingContextPrototypeFunctionCompileShader (exec=0x7ff2e0148350) at generated/JSWebGLRenderingContext.cpp:1502
#9  0x00007ff2e3b5e0e5 in ?? ()
#10 0x00007ff2e01482d0 in ?? ()
#11 0x00007ff33d5fded8 in llint_op_call () from /usr/lib/libQt5WebKit.so.5
#12 0x0000000000000001 in ?? ()
#13 0x41f0ffffffe00000 in ?? ()
#14 0x42e92c2c6bd14920 in ?? ()
#15 0x00007ff33d593b06 in JSC::JSStack::validateFence (this=0x50acb18, frame=0x7ff2e01482d0, function=<optimized out>, lineNo=<optimized out>) at interpreter/JSStackInlines.h:181
#16 0x00007ff2e3b5e260 in ?? ()
#17 0x0000000000c92770 in ?? ()
#18 0x00007ff2e01482c0 in ?? ()
#19 0x0000000000000000 in ?? ()