test: fix usdt undeclared function errors on mantis

Recently usage of undeclared functions became an error rather than a
warning, in C2x. https://reviews.llvm.org/D122983?id=420290

This change has migrated into the build tools of Ubuntu 23.10 which now
causes the USDT tests to fail to compile, see
https://github.com/bitcoin/bitcoin/issues/28600

Fix this by setting `-Wno-error=implicit-function-declaration` for the
tracing programs.

1 files changed, 5 insertions, 4 deletions

diff --git a/test/functional/interface_usdt_mempool.py b/test/functional/interface_usdt_mempool.py
index d1e274480c..0168d9f916 100755
--- a/test/functional/interface_usdt_mempool.py
+++ b/test/functional/interface_usdt_mempool.py
@@ -119,6 +119,7 @@ int trace_replaced(struct pt_regs *ctx) {
   replaced_events.perf_submit(ctx, &replaced, sizeof(replaced));
   return 0;
 }
+
 """
 
 
@@ -143,7 +144,7 @@ class MempoolTracepointTest(BitcoinTestFramework):
         node = self.nodes[0]
         ctx = USDT(pid=node.process.pid)
         ctx.enable_probe(probe="mempool:added", fn_name="trace_added")
-        bpf = BPF(text=MEMPOOL_TRACEPOINTS_PROGRAM, usdt_contexts=[ctx], debug=0)
+        bpf = BPF(text=MEMPOOL_TRACEPOINTS_PROGRAM, usdt_contexts=[ctx], debug=0, cflags=["-Wno-error=implicit-function-declaration"])
 
         def handle_added_event(_, data, __):
             events.append(bpf["added_events"].event(data))
@@ -180,7 +181,7 @@ class MempoolTracepointTest(BitcoinTestFramework):
         node = self.nodes[0]
         ctx = USDT(pid=node.process.pid)
         ctx.enable_probe(probe="mempool:removed", fn_name="trace_removed")
-        bpf = BPF(text=MEMPOOL_TRACEPOINTS_PROGRAM, usdt_contexts=[ctx], debug=0)
+        bpf = BPF(text=MEMPOOL_TRACEPOINTS_PROGRAM, usdt_contexts=[ctx], debug=0, cflags=["-Wno-error=implicit-function-declaration"])
 
         def handle_removed_event(_, data, __):
             events.append(bpf["removed_events"].event(data))
@@ -226,7 +227,7 @@ class MempoolTracepointTest(BitcoinTestFramework):
         node = self.nodes[0]
         ctx = USDT(pid=node.process.pid)
         ctx.enable_probe(probe="mempool:replaced", fn_name="trace_replaced")
-        bpf = BPF(text=MEMPOOL_TRACEPOINTS_PROGRAM, usdt_contexts=[ctx], debug=0)
+        bpf = BPF(text=MEMPOOL_TRACEPOINTS_PROGRAM, usdt_contexts=[ctx], debug=0, cflags=["-Wno-error=implicit-function-declaration"])
 
         def handle_replaced_event(_, data, __):
             events.append(bpf["replaced_events"].event(data))
@@ -277,7 +278,7 @@ class MempoolTracepointTest(BitcoinTestFramework):
         self.log.info("Hooking into mempool:rejected tracepoint...")
         ctx = USDT(pid=node.process.pid)
         ctx.enable_probe(probe="mempool:rejected", fn_name="trace_rejected")
-        bpf = BPF(text=MEMPOOL_TRACEPOINTS_PROGRAM, usdt_contexts=[ctx], debug=0)
+        bpf = BPF(text=MEMPOOL_TRACEPOINTS_PROGRAM, usdt_contexts=[ctx], debug=0, cflags=["-Wno-error=implicit-function-declaration"])
 
         def handle_rejected_event(_, data, __):
             events.append(bpf["rejected_events"].event(data))