The build of doc.cpp ends with "LLVM ERROR: out of memory" because c++
just gobbles up all the memory. That's probably a compiler bug. Using
-O1 avoids this problem and unlocks a few hundred ports by way of
qt6/qtdeclarative.

Index: Makefile
===================================================================
RCS file: /cvs/ports/x11/qt6/qtshadertools/Makefile,v
diff -u -p -r1.11 Makefile
--- Makefile	16 Nov 2024 06:55:00 -0000	1.11
+++ Makefile	20 Aug 2026 03:13:58 -0000
@@ -1,6 +1,7 @@
 QT6NAME =	QtShaderTools
 COMMENT =	Qt6 shader tools module
 PKGSPEC =	qt6-qtshadertools-${QT6_PKGSPEC}
+REVISION =	0
 
 SHARED_LIBS =  Qt6ShaderTools              3.0 # 6.7
 
Index: patches/patch-src_glslang_CMakeLists_txt
===================================================================
RCS file: patches/patch-src_glslang_CMakeLists_txt
diff -N patches/patch-src_glslang_CMakeLists_txt
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ patches/patch-src_glslang_CMakeLists_txt	20 Aug 2026 03:15:12 -0000
@@ -0,0 +1,13 @@
+build with libcxx22 runs out of memory with -O2
+
+Index: src/glslang/CMakeLists.txt
+--- src/glslang/CMakeLists.txt.orig
++++ src/glslang/CMakeLists.txt
+@@ -31,6 +31,7 @@ qt_internal_add_3rdparty_library(BundledGlslang_Spirv
+ )
+ qt_disable_warnings(BundledGlslang_Spirv)
+ qt_set_symbol_visibility_hidden(BundledGlslang_Spirv)
++set_source_files_properties(../3rdparty/glslang/SPIRV/doc.cpp PROPERTIES COMPILE_OPTIONS "-O1")
+ 
+ ## Scopes:
+ #####################################################################