diff --git a/src/add-ons/kernel/file_systems/bfs/Jamfile b/src/add-ons/kernel/file_systems/bfs/Jamfile
index b8842b9fab..8d78cf7bfd 100644
--- a/src/add-ons/kernel/file_systems/bfs/Jamfile
+++ b/src/add-ons/kernel/file_systems/bfs/Jamfile
@@ -7,6 +7,11 @@ SubDir HAIKU_TOP src add-ons kernel file_systems bfs ;
 		#BFS_BIG_ENDIAN_ONLY
 		;
 
+	if $(DEBUG) = 0 {
+		# the gcc on BeOS doesn't compile BFS correctly with -O2 or more
+		OPTIM = -O1 ;
+	}
+
 	defines = [ FDefines $(defines) ] ;
 	SubDirCcFlags $(defines) ;
 	SubDirC++Flags $(defines) ;
diff --git a/src/add-ons/kernel/file_systems/udf/drive_setup_addon/Jamfile b/src/add-ons/kernel/file_systems/udf/drive_setup_addon/Jamfile
index 40fc156d84..329a3ab981 100644
--- a/src/add-ons/kernel/file_systems/udf/drive_setup_addon/Jamfile
+++ b/src/add-ons/kernel/file_systems/udf/drive_setup_addon/Jamfile
@@ -1,5 +1,8 @@
 SubDir HAIKU_TOP src add-ons kernel file_systems udf drive_setup_addon ;
 
+# save original optimization level
+oldOPTIM = $(OPTIM) ;
+
 # set some additional defines
 {
 	local defines =
@@ -12,6 +15,9 @@ SubDir HAIKU_TOP src add-ons kernel file_systems udf drive_setup_addon ;
 
 	if $(DEBUG) {
 		#defines += DEBUG ;
+	} else {
+		# the gcc on BeOS doesn't compile BFS correctly with -O2 or more
+		OPTIM = -O1 ;
 	}
 
 	defines = [ FDefines $(defines) ] ;
@@ -49,3 +55,7 @@ actions ignore InstallUDFDS
 }
 
 InstallUDFDS install : i-udf-ds ;
+
+# restore original optimization level
+OPTIM = $(oldOPTIM) ;
+
diff --git a/src/tests/add-ons/kernel/file_systems/bfs/r5/Jamfile b/src/tests/add-ons/kernel/file_systems/bfs/r5/Jamfile
index 882568e2ff..7a22934a15 100644
--- a/src/tests/add-ons/kernel/file_systems/bfs/r5/Jamfile
+++ b/src/tests/add-ons/kernel/file_systems/bfs/r5/Jamfile
@@ -2,6 +2,9 @@ SubDir HAIKU_TOP src tests add-ons kernel file_systems bfs r5 ;
 
 SetSubDirSupportedPlatformsBeOSCompatible ;
 
+# save original optimization level
+oldOPTIM = $(OPTIM) ;
+
 # set some additional defines
 {
 	local defines =
@@ -24,6 +27,11 @@ SetSubDirSupportedPlatformsBeOSCompatible ;
 		bfsAddOnName = obfs ;
 	}
 
+	if $(DEBUG) = 0 {
+		# the gcc on BeOS doesn't compile BFS correctly with -O2 or more
+		OPTIM = -O1 ;
+	}
+
 	defines = [ FDefines $(defines) ] ;
 	SubDirCcFlags $(defines) ;
 	SubDirC++Flags $(defines) -fno-rtti ;
@@ -67,3 +75,6 @@ actions ignore InstallBFS
 }
 
 InstallBFS install : obfs ;
+
+# restore original optimization level
+OPTIM = $(oldOPTIM) ;
diff --git a/src/tests/add-ons/kernel/file_systems/udf/r5/Jamfile b/src/tests/add-ons/kernel/file_systems/udf/r5/Jamfile
index 53c24abf51..d94a504fa7 100644
--- a/src/tests/add-ons/kernel/file_systems/udf/r5/Jamfile
+++ b/src/tests/add-ons/kernel/file_systems/udf/r5/Jamfile
@@ -3,6 +3,9 @@ SubDir HAIKU_TOP src tests add-ons kernel file_systems udf r5 ;
 SetSubDirSupportedPlatformsBeOSCompatible ;
 SubDirC++Flags -fno-rtti ;
 
+# save original optimization level
+oldOPTIM = $(OPTIM) ;
+
 # set some additional defines
 {
 	local defines =
@@ -11,6 +14,11 @@ SubDirC++Flags -fno-rtti ;
 
 	defines += COMPILE_FOR_R5 ;
 
+	if $(DEBUG) = 0 {
+		# the gcc on BeOS doesn't compile BFS correctly with -O2 or more
+		OPTIM = -O1 ;
+	}
+
 	defines = [ FDefines $(defines) ] ;
 	SubDirCcFlags $(defines) ;
 	SubDirC++Flags $(defines) ;
@@ -54,3 +62,8 @@ actions ignore InstallUDF
 }
 
 InstallUDF install : udf ;
+
+# restore original optimization level
+OPTIM = $(oldOPTIM) ;
+
+SubInclude HAIKU_TOP src tests add-ons kernel file_systems udf r5 drive_setup_addon ;
diff --git a/src/tests/add-ons/kernel/file_systems/udf/r5/drive_setup_addon/Jamfile b/src/tests/add-ons/kernel/file_systems/udf/r5/drive_setup_addon/Jamfile
index e8829295c8..8289920b43 100644
--- a/src/tests/add-ons/kernel/file_systems/udf/r5/drive_setup_addon/Jamfile
+++ b/src/tests/add-ons/kernel/file_systems/udf/r5/drive_setup_addon/Jamfile
@@ -2,6 +2,9 @@ SubDir HAIKU_TOP src tests add-ons kernel file_systems udf r5 drive_setup_addon
 
 SetSubDirSupportedPlatformsBeOSCompatible ;
 
+# save original optimization level
+oldOPTIM = $(OPTIM) ;
+
 # set some additional defines
 {
 	local defines =
@@ -14,6 +17,9 @@ SetSubDirSupportedPlatformsBeOSCompatible ;
 
 	if $(DEBUG) {
 		#defines += DEBUG ;
+	} else {
+		# the gcc on BeOS doesn't compile BFS correctly with -O2 or more
+		OPTIM = -O1 ;
 	}
 
 	defines = [ FDefines $(defines) ] ;
@@ -51,3 +57,7 @@ actions ignore InstallUDFDS
 }
 
 InstallUDFDS install : i-udf-ds ;
+
+# restore original optimization level
+OPTIM = $(oldOPTIM) ;
+
diff --git a/src/tests/add-ons/kernel/file_systems/userlandfs/bfs/Jamfile b/src/tests/add-ons/kernel/file_systems/userlandfs/bfs/Jamfile
index 28128f82c8..b42a2d0349 100644
--- a/src/tests/add-ons/kernel/file_systems/userlandfs/bfs/Jamfile
+++ b/src/tests/add-ons/kernel/file_systems/userlandfs/bfs/Jamfile
@@ -11,6 +11,11 @@ SEARCH_SOURCE += $(bfsTop) ;
 		USER=1
 	;
 
+	if $(DEBUG) = 0 {
+		# the gcc on BeOS doesn't compile BFS correctly with -O2 or more
+		OPTIM = -O1 ;
+	}
+
 	defines = [ FDefines $(defines) ] ;
 	SubDirCcFlags $(defines) ;
 	SubDirC++Flags $(defines) -fno-rtti ;
diff --git a/src/tools/bfs_shell/Jamfile b/src/tools/bfs_shell/Jamfile
index 0c02396e7d..bd8fb28849 100644
--- a/src/tools/bfs_shell/Jamfile
+++ b/src/tools/bfs_shell/Jamfile
@@ -12,6 +12,11 @@ DEFINES += HAIKU_BUILD_COMPATIBILITY_H ;
 		FS_SHELL
 		;
 
+	if $(DEBUG) = 0 {
+		# the gcc on BeOS doesn't compile BFS correctly with -O2 or more
+		OPTIM = -O1 ;
+	}
+
 	defines = [ FDefines $(defines) ] ;
 	SubDirCcFlags $(defines) -Wno-multichar ;
 	SubDirC++Flags $(defines) -Wno-multichar -fno-rtti ;