diff --git a/bolt/test/X86/fallthrough-to-noop.test b/bolt/test/X86/fallthrough-to-noop.test
--- a/bolt/test/X86/fallthrough-to-noop.test
+++ b/bolt/test/X86/fallthrough-to-noop.test
@@ -3,7 +3,7 @@
 
 RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown \
 RUN:   %S/Inputs/ft_to_noop.s -o %t.o
-RUN: link_fdata %S/Inputs/ft_to_noop.s %t.o %t.fdata
+RUN: link_fdata %S/Inputs/ft_to_noop.s %t.o %t.fdata --nmtool llvm-nm
 RUN: llvm-strip --strip-unneeded %t.o
 RUN: %clang %cflags %t.o -o %t.exe -Wl,-q
 RUN: llvm-bolt %t.exe -o %t -data %t.fdata \
diff --git a/bolt/test/X86/jump-table-footprint-reduction.test b/bolt/test/X86/jump-table-footprint-reduction.test
--- a/bolt/test/X86/jump-table-footprint-reduction.test
+++ b/bolt/test/X86/jump-table-footprint-reduction.test
@@ -3,7 +3,7 @@
 
 RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown \
 RUN:   %S/Inputs/jump_table_footprint_reduction.s -o %t.o
-RUN: link_fdata %S/Inputs/jump_table_footprint_reduction.s %t.o %t.fdata
+RUN: link_fdata %S/Inputs/jump_table_footprint_reduction.s %t.o %t.fdata --nmtool llvm-nm
 RUN: llvm-strip --strip-unneeded %t.o
 RUN: %clang %cflags -no-pie %t.o -o %t.exe -Wl,-q
 RUN: llvm-bolt %t.exe -data %t.fdata -o /dev/null \
diff --git a/bolt/test/X86/jump-table-icp.test b/bolt/test/X86/jump-table-icp.test
--- a/bolt/test/X86/jump-table-icp.test
+++ b/bolt/test/X86/jump-table-icp.test
@@ -1,6 +1,6 @@
 RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown \
 RUN:   %p/Inputs/jump_table_icp.s -o %t.o
-RUN: link_fdata %p/Inputs/jump_table_icp.s %t.o %t.fdata 
+RUN: link_fdata %p/Inputs/jump_table_icp.s %t.o %t.fdata --nmtool llvm-nm
 RUN: llvm-strip --strip-unneeded %t.o
 RUN: %clang %cflags -no-pie %t.o -o %t.exe -Wl,-q
 
diff --git a/bolt/test/X86/loop-nest.test b/bolt/test/X86/loop-nest.test
--- a/bolt/test/X86/loop-nest.test
+++ b/bolt/test/X86/loop-nest.test
@@ -2,7 +2,7 @@
 
 RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown \
 RUN:   %p/Inputs/loop_nest.s -o %t.o
-RUN: link_fdata %p/Inputs/loop_nest.s %t.o %t.fdata
+RUN: link_fdata %p/Inputs/loop_nest.s %t.o %t.fdata --nmtool llvm-nm
 RUN: llvm-strip --strip-unneeded %t.o
 RUN: %clang %cflags -no-pie %t.o -o %t.exe -Wl,-q
 
diff --git a/bolt/test/X86/merge-fdata-bat-mode.test b/bolt/test/X86/merge-fdata-bat-mode.test
--- a/bolt/test/X86/merge-fdata-bat-mode.test
+++ b/bolt/test/X86/merge-fdata-bat-mode.test
@@ -1,11 +1,8 @@
 # Check merge-fdata tool correctly processes fdata files with header strings
 # such as the ones produced by BAT mode (boltedcollection)
 RUN: merge-fdata %S/Inputs/bat_profile_1.fdata \
-RUN:             %S/Inputs/bat_profile_2.fdata 2> %t.error \
+RUN:             %S/Inputs/bat_profile_2.fdata \
 RUN:   | FileCheck %s --check-prefix=CHECK-FDATA
-RUN: cat %t.error |& FileCheck %s --check-prefix=CHECK-ERROR
-
-CHECK-ERROR-NOT:  Malformed
 
 CHECK-FDATA: 1 main 451 1 SolveCubic 0 0 302
 
diff --git a/bolt/test/X86/no-entry-reordering.test b/bolt/test/X86/no-entry-reordering.test
--- a/bolt/test/X86/no-entry-reordering.test
+++ b/bolt/test/X86/no-entry-reordering.test
@@ -2,7 +2,7 @@
 # entry point even if there is a hot edge from a block to entry point
 
 RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown %S/Inputs/entry.s -o %t.o
-RUN: link_fdata %S/Inputs/entry.s %t.o %t.fdata
+RUN: link_fdata %S/Inputs/entry.s %t.o %t.fdata --nmtool llvm-nm
 RUN: llvm-strip --strip-unneeded %t.o
 RUN: %clang %cflags %t.o -o %t.exe -Wl,-q -nostdlib
 RUN: llvm-bolt %t.exe -data %t.fdata -o /dev/null -reorder-blocks=normal \
diff --git a/bolt/test/X86/remove-unused.test b/bolt/test/X86/remove-unused.test
--- a/bolt/test/X86/remove-unused.test
+++ b/bolt/test/X86/remove-unused.test
@@ -2,7 +2,7 @@
 # the BB reordering ignores dead BBs.
 
 RUN: llvm-mc -filetype=obj -triple x86_64-unknown-unknown %S/Inputs/entry.s -o %t.o
-RUN: link_fdata %S/Inputs/entry.s %t.o %t.fdata
+RUN: link_fdata %S/Inputs/entry.s %t.o %t.fdata --nmtool llvm-nm
 RUN: llvm-strip --strip-unneeded %t.o
 RUN: %clang %cflags %t.o -o %t.exe -Wl,-q -nostdlib
 RUN: llvm-bolt %t.exe -data %t.fdata -o %t -funcs=_start \
diff --git a/bolt/test/link_fdata.py b/bolt/test/link_fdata.py
--- a/bolt/test/link_fdata.py
+++ b/bolt/test/link_fdata.py
@@ -98,7 +98,7 @@
     assert symname in symbols, f"ERROR: symbol {symname} is not defined in binary"
     return symbols[symname]
 
-with open(args.output, 'w') as f:
+with open(args.output, 'w', newline='\n') as f:
     for etype, expr in exprs:
         if etype == 'FDATA':
             issym1, anchor1, offsym1, issym2, anchor2, offsym2, execnt, mispred = expr
diff --git a/bolt/test/lit.cfg.py b/bolt/test/lit.cfg.py
--- a/bolt/test/lit.cfg.py
+++ b/bolt/test/lit.cfg.py
@@ -88,7 +88,7 @@
     ToolSubst('llvm-objcopy', unresolved='fatal'),
     ToolSubst('llvm-strip', unresolved='fatal'),
     ToolSubst('llvm-readelf', unresolved='fatal'),
-    ToolSubst('link_fdata', command=link_fdata_cmd, unresolved='fatal'),
+    ToolSubst('link_fdata', command=sys.executable, unresolved='fatal', extra_args=[link_fdata_cmd]),
     ToolSubst('merge-fdata', unresolved='fatal'),
     ToolSubst('llvm-readobj', unresolved='fatal'),
 ]