Example of conversion errors for XML to ICC to XML to ICC

[xsscx]

Maintainer Repro

Sat Jan 24 03:10:25 AM UTC 2026

Given a single XML File, test the conversion fidelity for XML to ICC to XML to ICC and Report.

Reproduction

Step 1. iccFromXml input.xml input-1.icc
Profile parsed. Profile is invalid, but saved correctly

Step 2. iccToXml input-1.icc input-1.xml
XML successfully created

Step 3. iccFromXml input-1.xml input-2.icc

Unexpected Output

iccFromXml input-1.xml input-2.icc

input-1.xml:64792: parser error : xmlSAX2Characters: huge text node
                              0.000000000000 0.000000000000 0.000000000000 0.000
    ^
input-1.xml:64792: parser error : Extra content at the end of the document
                              0.000000000000 0.000000000000 0.000000000000 0.000
                              ^

Unable to Parse 'input-1.xml'

Unexpected File Size

Given a single XML File of 3.3M the returned XML is 12M.

ls -lah input.xml input-1.xml
-rw-rw-r-- 1 xss xss  12M Jan 24 03:08 input-1.xml
-rw-rw-r-- 1 xss xss 3.3M Jan 24 02:39 input.xml

Expected Output

Similar Inputs & Outputs

Caveat: Exact corruption varies by compiler, platform, and optimization level

input.xml

[xsscx]

NaN Issues when converting XML to ICC to XML

Example:

Original XML: <XYZNumber X="4.967254638672" Y="-32768.000000000000" Z="0.813827514648"/>
Returned XML: <XYZNumber X="4.967253650941049" Y="-nan000000" Z="0.813829270318576"/>

The input Y="-32768.000000000000" is causing UB.
The returned Y="-nan000000" is causing UB.

• UB runtime error in <class T, icTagTypeSignature Tsig> at IccLibXML/IccUtilXml.cpp:1044 #532
• UB runtime error in icVectorApplyMatrix3x3() at IccProfLib/IccUtil.cpp:560 #529
• https://github.com/InternationalColorConsortium/iccDEV/issues?q=is%3Aissue%20state%3Aclosed%20outside%20range

Invalid XML from ICC Blob

ICC Parser emits: Y="-nan000000" to XML parser, further processing results with a UB NaN

Sample Impact

Tag name truncation

<DataColourSpace>NULL</DataColourSpace>
---
ataColourSpace>

Attribute name mangling

GlossyOrMatte="glossy"
---
GlossyOrMattaColour="colour"

Struct field misalignment

Time field replaced:

<CreationDateTime>2026-01-25T22:49:22</CreationDateTime>
---
<CreationDateTime>now</CreationDateTime>