gh-139588: Docs: fix PDF build

Author: m-aciek

Doc/Makefile

@@ -88,6 +88,7 @@ htmlhelp: build
 	      "build/htmlhelp/pydoc.hhp project file."
 
 .PHONY: latex
+latex: _ensure-sphinxcontrib-svg2pdfconverter
 latex: BUILDER = latex
 latex: build
 	@echo "Build finished; the LaTeX files are in build/latex."
@@ -231,7 +232,7 @@ dist-text:
 	@echo "Build finished and archived!"
 
 .PHONY: dist-pdf
-dist-pdf:
+dist-pdf: _ensure-sphinxcontrib-svg2pdfconverter
 	# archive the A4 latex
 	@echo "Building LaTeX (A4 paper)..."
 	mkdir -p dist
@@ -292,6 +293,10 @@ _ensure-pre-commit:
 _ensure-sphinx-autobuild:
 	$(MAKE) _ensure-package PACKAGE=sphinx-autobuild
 
+.PHONY: _ensure-sphinxcontrib-svg2pdfconverter
+_ensure-sphinxcontrib-svg2pdfconverter:
+	$(MAKE) _ensure-package PACKAGE=sphinxcontrib-svg2pdfconverter
+
 .PHONY: check
 check: _ensure-pre-commit
 	$(VENVDIR)/bin/python3 -m pre_commit run --all-files

Doc/conf.py

@@ -45,6 +45,7 @@
     'linklint.ext',
     'notfound.extension',
     'sphinxext.opengraph',
+    'sphinxcontrib.rsvgconverter',
 )
 for optional_ext in _OPTIONAL_EXTENSIONS:
     try: