From d74424cb3780284a989b1784a984003bd68e4ed4 Mon Sep 17 00:00:00 2001
From: pat-s <patrick.schratz@gmail.com>
Date: Sun, 19 Jul 2026 08:39:53 +0000
Subject: [PATCH] fix(patches): build RcppParallel against system oneTBB
 instead of disabling TBB

The disable-tbb patch skipped the bundled Intel TBB build by forcing the
TinyThread backend, which also stripped RcppParallel's TBB linkage. That
broke every dependent that links TBB through RcppParallelLibs() (rstan and
the whole Stan cluster) with 'symbol not found: tbb::detail::r1::observe'.

Replace it with system-tbb.patch: leave USE_TBB unset (so the bundled build
is skipped on musl and g++ 15) but keep the TBB backend and link the system
oneTBB that the build-env images now ship. RcppParallelLibs() then hands the
system-TBB link flags to dependents, provided TBB_INC/TBB_LIB are exported in
the images (added separately in build-env-images).

Verified in the build-env-alpine:3.24 image: RcppParallel builds against
oneTBB 2022 with no ABI errors, and rstan links (-ltbb -ltbbmalloc) and
loads without the missing-symbol error.
---
 local/patches/RcppParallel/disable-tbb.patch | 16 ----------------
 local/patches/RcppParallel/system-tbb.patch  | 19 +++++++++++++++++++
 local/patches/registry.json                  | 17 ++++++++++++-----
 3 files changed, 31 insertions(+), 21 deletions(-)
 delete mode 100644 local/patches/RcppParallel/disable-tbb.patch
 create mode 100644 local/patches/RcppParallel/system-tbb.patch

diff --git a/local/patches/RcppParallel/disable-tbb.patch b/local/patches/RcppParallel/disable-tbb.patch
deleted file mode 100644
index 0fe8ad9..0000000
--- a/local/patches/RcppParallel/disable-tbb.patch
+++ /dev/null
@@ -1,16 +0,0 @@
-diff --git a/src/Makevars.in b/src/Makevars.in
-index be8445f..faee771 100644
---- a/src/Makevars.in
-+++ b/src/Makevars.in
-@@ -60,7 +60,10 @@ else
- 	endif
- 
- 	ifeq ($(UNAME), Linux)
--		USE_TBB=Linux
-+		# bincraft patch: the bundled Intel TBB build hangs/fails on musl (Alpine)
-+		# and newer toolchains (g++ 15). Skip it (leave USE_TBB unset) and force the
-+		# TinyThread backend so RcppParallel still builds.
-+		PKG_CXXFLAGS += -DRCPP_PARALLEL_USE_TBB=0
- 	endif
- 
- 	ifeq ($(UNAME), SunOS)
diff --git a/local/patches/RcppParallel/system-tbb.patch b/local/patches/RcppParallel/system-tbb.patch
new file mode 100644
index 0000000..263a593
--- /dev/null
+++ b/local/patches/RcppParallel/system-tbb.patch
@@ -0,0 +1,19 @@
+diff --git a/src/Makevars.in b/src/Makevars.in
+index be8445f..7cb6c9e 100644
+--- a/src/Makevars.in
++++ b/src/Makevars.in
+@@ -60,7 +60,13 @@ else
+ 	endif
+ 
+ 	ifeq ($(UNAME), Linux)
+-		USE_TBB=Linux
++		# bincraft patch: link the system oneTBB (installed in the build-env images)
++		# instead of building the bundled Intel TBB, which fails on musl (Alpine) and
++		# newer toolchains (g++ 15). Leaving USE_TBB unset skips the bundled build;
++		# -DRCPP_PARALLEL_USE_TBB=1 keeps the TBB backend so dependents (rstan, ...)
++		# link TBB, and -ltbb/-ltbbmalloc pull the system library from default paths.
++		PKG_CXXFLAGS += -DRCPP_PARALLEL_USE_TBB=1 -DTBB_SUPPRESS_DEPRECATED_MESSAGES=1 -DTBB_INTERFACE_NEW
++		PKG_LIBS += -ltbb -ltbbmalloc
+ 	endif
+ 
+ 	ifeq ($(UNAME), SunOS)
diff --git a/local/patches/registry.json b/local/patches/registry.json
index e53f1c9..c446fda 100644
--- a/local/patches/registry.json
+++ b/local/patches/registry.json
@@ -2,17 +2,22 @@
   {
     "package": "RcppParallel",
     "versions": "*",
-    "platforms": ["alpine", "ubuntu-2604"],
+    "platforms": [
+      "alpine",
+      "ubuntu-2604"
+    ],
     "env": {},
     "configure_args": [],
     "makevars": {},
-    "patch": "RcppParallel/disable-tbb.patch",
-    "reason": "bundled Intel TBB build hangs/fails on musl (Alpine) and newer toolchains (g++ 15 on ubuntu-2604); patch unsets USE_TBB and forces -DRCPP_PARALLEL_USE_TBB=0 so RcppParallel skips the bundled build and uses the TinyThread backend"
+    "patch": "RcppParallel/system-tbb.patch",
+    "reason": "bundled Intel TBB build hangs/fails on musl (Alpine) and newer toolchains (g++ 15 on ubuntu-2604); link the system oneTBB (now in the build-env images) instead, keeping the TBB backend so dependents (rstan, ...) link TBB"
   },
   {
     "package": "fs",
     "versions": "*",
-    "platforms": ["*"],
+    "platforms": [
+      "*"
+    ],
     "env": {},
     "configure_args": [],
     "makevars": {},
@@ -22,7 +27,9 @@
   {
     "package": "rstan",
     "versions": "*",
-    "platforms": ["*"],
+    "platforms": [
+      "*"
+    ],
     "env": {},
     "configure_args": [],
     "makevars": {
-- 
2.54.0