Exclude scalbnf.c from LTO

Continuation of #15497

Fixes: #19781

Author: sbc100

.circleci/config.yml

@@ -522,6 +522,7 @@ jobs:
           title: "core3+extras"
           test_targets: "
             lto2.test_dylink_syslibs_all
+            lto2.test_float_builtins
             lto0.test_exceptions_allowed_uncaught
             core3
             core2g.test_externref

test/core/test_float_builtins.c

@@ -34,6 +34,7 @@ int test_builtins() {
   TEST(fmin)
   TEST(fmod)
   TEST(scalbn)
+  TEST(ldexp)
 
   TEST(pow)
   TESTI(powi)

test/core/test_float_builtins.out

@@ -3,6 +3,7 @@ __builtin_fmax 0.567800 : 1.010100 : 12.012300
 __builtin_fmin 0.123400 : 0.101010 : 3.320100
 __builtin_fmod 0.123400 : 0.101010 : 2.052000
 __builtin_scalbn 0.123400 : 1.010100 : 96.098400
+__builtin_ldexp 0.123400 : 1.010100 : 96.098400
 __builtin_pow 0.304824 : 1.001016 : 3841.199350
 __builtin_powi 0.000000 : 2.421390 : 101648962858951235671184182497867417669061891127967232769386628692937206561802464554722378383360.000000
 inf : 3.091515 : 3.091515 : 1

tools/system_libs.py

@@ -969,7 +969,8 @@ def get_libcall_files(self):
       '__math_oflow.c', '__math_oflowf.c',
       '__math_uflow.c', '__math_uflowf.c',
       '__math_invalid.c', '__math_invalidf.c', '__math_invalidl.c',
-      'pow.c', 'pow_data.c', 'log.c', 'log_data.c', 'log2.c', 'log2_data.c'
+      'pow.c', 'pow_data.c', 'log.c', 'log_data.c', 'log2.c', 'log2_data.c',
+      'scalbnf.c',
     ]
     math_files = files_in_path(path='system/lib/libc/musl/src/math', filenames=math_files)