kbuild: set EXIT trap before creating temporary directory

Swap the order of 'mkdir' and 'trap' just in case the subshell is
interrupted between 'mkdir' and 'trap' although the effect might be
subtle.

This does not intend to make the cleanup perfect. There are more cases
that miss to remove the tmp directory, for example:

 - When interrupted, dash does not invoke the EXIT trap (bash does)

 - 'rm' command might be interrupted before removing the directory

I am not addressing all the cases since the tmp directory is harmless
after all.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>

diff --git a/scripts/Kconfig.include b/scripts/Kconfig.include
index c1f4222..a0ccceb 100644 (file)
--- a/scripts/Kconfig.include
+++ b/scripts/Kconfig.include
@@ -25,7 +25,7 @@ failure = $(if-success,$(1),n,y)
 
 # $(cc-option,<flag>)
 # Return y if the compiler supports <flag>, n otherwise
-cc-option = $(success,mkdir .tmp_$$; trap "rm -rf .tmp_$$" EXIT; $(CC) -Werror $(CLANG_FLAGS) $(1) -c -x c /dev/null -o .tmp_$$/tmp.o)
+cc-option = $(success,trap "rm -rf .tmp_$$" EXIT; mkdir .tmp_$$; $(CC) -Werror $(CLANG_FLAGS) $(1) -c -x c /dev/null -o .tmp_$$/tmp.o)
 
 # $(ld-option,<flag>)
 # Return y if the linker supports <flag>, n otherwise

diff --git a/scripts/Makefile.compiler b/scripts/Makefile.compiler
index 86ecd2a..94d0d40 100644 (file)
--- a/scripts/Makefile.compiler
+++ b/scripts/Makefile.compiler
@@ -21,8 +21,8 @@ TMPOUT = $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_$$$$
 # automatically cleaned up.
 try-run = $(shell set -e;              \
        TMP=$(TMPOUT)/tmp;              \
-       mkdir -p $(TMPOUT);             \
        trap "rm -rf $(TMPOUT)" EXIT;   \
+       mkdir -p $(TMPOUT);             \
        if ($(1)) >/dev/null 2>&1;      \
        then echo "$(2)";               \
        else echo "$(3)";               \