[PATCH v3 0/3] BaseTools: fix gcc workaround

[PATCH v3 0/3] BaseTools: fix gcc workaround

[Gerd Hoffmann]

The linux kernel has a bunch of useful macros to check whenever a given
compiler supports specific flags.  Import them, adapt them for edk2, then
put them into use to make both gcc5 and gcc12 work for BaseTools.

Gerd Hoffmann (3):
  BaseTools: import compiler check macros from linux kernel
  BaseTools: adapt comniler checks mmacros for edk2
  BaseTools: fix gcc workaround

 BaseTools/Source/C/DevicePath/GNUmakefile     |  3 +-
 .../Source/C/Makefiles/compiler.makefile      | 76 +++++++++++++++++++
 2 files changed, 78 insertions(+), 1 deletion(-)
 create mode 100644 BaseTools/Source/C/Makefiles/compiler.makefile

-- 
2.35.1

[PATCH v3 1/3] BaseTools: import compiler check macros from linux kernel

[Gerd Hoffmann]

Makefile functions to check for compiler flags supported.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 .../Source/C/Makefiles/compiler.makefile      | 76 +++++++++++++++++++
 1 file changed, 76 insertions(+)
 create mode 100644 BaseTools/Source/C/Makefiles/compiler.makefile

diff --git a/BaseTools/Source/C/Makefiles/compiler.makefile b/BaseTools/Source/C/Makefiles/compiler.makefile
new file mode 100644
index 000000000000..b575391c08d6
--- /dev/null
+++ b/BaseTools/Source/C/Makefiles/compiler.makefile
@@ -0,0 +1,76 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+# copy from linux kernel soure tree (scripts/Makefile.compiler)
+
+# cc-cross-prefix
+# Usage: CROSS_COMPILE := $(call cc-cross-prefix, m68k-linux-gnu- m68k-linux-)
+# Return first <prefix> where a <prefix>gcc is found in PATH.
+# If no gcc found in PATH with listed prefixes return nothing
+#
+# Note: '2>/dev/null' is here to force Make to invoke a shell. Otherwise, it
+# would try to directly execute the shell builtin 'command'. This workaround
+# should be kept for a long time since this issue was fixed only after the
+# GNU Make 4.2.1 release.
+cc-cross-prefix = $(firstword $(foreach c, $(1), \
+			$(if $(shell command -v -- $(c)gcc 2>/dev/null), $(c))))
+
+# output directory for tests below
+TMPOUT = $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_$$$$
+
+# try-run
+# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
+# Exit code chooses option. "$$TMP" serves as a temporary file and is
+# automatically cleaned up.
+try-run = $(shell set -e;		\
+	TMP=$(TMPOUT)/tmp;		\
+	mkdir -p $(TMPOUT);		\
+	trap "rm -rf $(TMPOUT)" EXIT;	\
+	if ($(1)) >/dev/null 2>&1;	\
+	then echo "$(2)";		\
+	else echo "$(3)";		\
+	fi)
+
+# as-option
+# Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
+
+as-option = $(call try-run,\
+	$(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
+
+# as-instr
+# Usage: cflags-y += $(call as-instr,instr,option1,option2)
+
+as-instr = $(call try-run,\
+	printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
+
+# __cc-option
+# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586)
+__cc-option = $(call try-run,\
+	$(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4))
+
+# cc-option
+# Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
+
+cc-option = $(call __cc-option, $(CC),\
+	$(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS),$(1),$(2))
+
+# cc-option-yn
+# Usage: flag := $(call cc-option-yn,-march=winchip-c6)
+cc-option-yn = $(call try-run,\
+	$(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
+
+# cc-disable-warning
+# Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
+cc-disable-warning = $(call try-run,\
+	$(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
+
+# cc-ifversion
+# Usage:  EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
+cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || echo $(4))
+
+# ld-option
+# Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
+ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
+
+# ld-ifversion
+# Usage:  $(call ld-ifversion, -ge, 22252, y)
+ld-ifversion = $(shell [ $(CONFIG_LD_VERSION)0 $(1) $(2)0 ] && echo $(3) || echo $(4))
-- 
2.35.1

[PATCH v3 2/3] BaseTools: adapt comniler checks mmacros for edk2

[Gerd Hoffmann]

edk2 BaseTools use BUILD_CC not CC.  Update the check macros
accordingly so they actually work with BaseTools.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 BaseTools/Source/C/Makefiles/compiler.makefile | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/BaseTools/Source/C/Makefiles/compiler.makefile b/BaseTools/Source/C/Makefiles/compiler.makefile
index b575391c08d6..3337857ca9c5 100644
--- a/BaseTools/Source/C/Makefiles/compiler.makefile
+++ b/BaseTools/Source/C/Makefiles/compiler.makefile
@@ -18,7 +18,7 @@ cc-cross-prefix = $(firstword $(foreach c, $(1), \
 TMPOUT = $(if $(KBUILD_EXTMOD),$(firstword $(KBUILD_EXTMOD))/).tmp_$$$$
 
 # try-run
-# Usage: option = $(call try-run, $(CC)...-o "$$TMP",option-ok,otherwise)
+# Usage: option = $(call try-run, $(BUILD_CC)...-o "$$TMP",option-ok,otherwise)
 # Exit code chooses option. "$$TMP" serves as a temporary file and is
 # automatically cleaned up.
 try-run = $(shell set -e;		\
@@ -34,34 +34,34 @@ try-run = $(shell set -e;		\
 # Usage: cflags-y += $(call as-option,-Wa$(comma)-isa=foo,)
 
 as-option = $(call try-run,\
-	$(CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
+	$(BUILD_CC) $(KBUILD_CFLAGS) $(1) -c -x assembler /dev/null -o "$$TMP",$(1),$(2))
 
 # as-instr
 # Usage: cflags-y += $(call as-instr,instr,option1,option2)
 
 as-instr = $(call try-run,\
-	printf "%b\n" "$(1)" | $(CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
+	printf "%b\n" "$(1)" | $(BUILD_CC) $(KBUILD_AFLAGS) -c -x assembler -o "$$TMP" -,$(2),$(3))
 
 # __cc-option
-# Usage: MY_CFLAGS += $(call __cc-option,$(CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586)
+# Usage: MY_CFLAGS += $(call __cc-option,$(BUILD_CC),$(MY_CFLAGS),-march=winchip-c6,-march=i586)
 __cc-option = $(call try-run,\
 	$(1) -Werror $(2) $(3) -c -x c /dev/null -o "$$TMP",$(3),$(4))
 
 # cc-option
 # Usage: cflags-y += $(call cc-option,-march=winchip-c6,-march=i586)
 
-cc-option = $(call __cc-option, $(CC),\
+cc-option = $(call __cc-option, $(BUILD_CC),\
 	$(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS),$(1),$(2))
 
 # cc-option-yn
 # Usage: flag := $(call cc-option-yn,-march=winchip-c6)
 cc-option-yn = $(call try-run,\
-	$(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
+	$(BUILD_CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(1) -c -x c /dev/null -o "$$TMP",y,n)
 
 # cc-disable-warning
 # Usage: cflags-y += $(call cc-disable-warning,unused-but-set-variable)
 cc-disable-warning = $(call try-run,\
-	$(CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
+	$(BUILD_CC) -Werror $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -W$(strip $(1)) -c -x c /dev/null -o "$$TMP",-Wno-$(strip $(1)))
 
 # cc-ifversion
 # Usage:  EXTRA_CFLAGS += $(call cc-ifversion, -lt, 0402, -O1)
@@ -69,7 +69,7 @@ cc-ifversion = $(shell [ $(CONFIG_GCC_VERSION)0 $(1) $(2)000 ] && echo $(3) || e
 
 # ld-option
 # Usage: KBUILD_LDFLAGS += $(call ld-option, -X, -Y)
-ld-option = $(call try-run, $(LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
+ld-option = $(call try-run, $(BUILD_LD) $(KBUILD_LDFLAGS) $(1) -v,$(1),$(2),$(3))
 
 # ld-ifversion
 # Usage:  $(call ld-ifversion, -ge, 22252, y)
-- 
2.35.1

[PATCH v3 3/3] BaseTools: fix gcc workaround

[Gerd Hoffmann]

Check whenever the compiler used knows the warning we want disable.

Fixes: 22130dcd98b4 ("Basetools: turn off gcc12 warning")
Reported-by: Rebecca Cran <rebecca@bsdio.com>
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
---
 BaseTools/Source/C/DevicePath/GNUmakefile | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/BaseTools/Source/C/DevicePath/GNUmakefile b/BaseTools/Source/C/DevicePath/GNUmakefile
index b05d2bddfa68..1cc966c4831f 100644
--- a/BaseTools/Source/C/DevicePath/GNUmakefile
+++ b/BaseTools/Source/C/DevicePath/GNUmakefile
@@ -12,9 +12,10 @@ APPNAME = DevicePath
 OBJECTS = DevicePath.o UefiDevicePathLib.o DevicePathFromText.o  DevicePathUtilities.o
 
 include $(MAKEROOT)/Makefiles/app.makefile
+include $(MAKEROOT)/Makefiles/compiler.makefile
 
 # gcc 12 trips over device path handling
-BUILD_CFLAGS += -Wno-error=stringop-overflow
+BUILD_CFLAGS += $(call cc-disable-warning,stringop-overflow)
 
 LIBS = -lCommon
 ifeq ($(CYGWIN), CYGWIN)
-- 
2.35.1

Re: [edk2-devel] [PATCH v3 0/3] BaseTools: fix gcc workaround

[Pedro Falcato]

[-- Attachment #1: Type: text/plain, Size: 972 bytes --]

Hi Gerd,

These patches are a great idea but I don't know if we can take GPLv2 code
like that. Are they even mergeable into the main edk2 repo (as it's not
compatible with BSD-2-clause)?

Thanks,
Pedro

On Mon, Apr 4, 2022 at 10:32 AM Gerd Hoffmann <kraxel@redhat.com> wrote:

> The linux kernel has a bunch of useful macros to check whenever a given
> compiler supports specific flags.  Import them, adapt them for edk2, then
> put them into use to make both gcc5 and gcc12 work for BaseTools.
>
> Gerd Hoffmann (3):
>   BaseTools: import compiler check macros from linux kernel
>   BaseTools: adapt comniler checks mmacros for edk2
>   BaseTools: fix gcc workaround
>
>  BaseTools/Source/C/DevicePath/GNUmakefile     |  3 +-
>  .../Source/C/Makefiles/compiler.makefile      | 76 +++++++++++++++++++
>  2 files changed, 78 insertions(+), 1 deletion(-)
>  create mode 100644 BaseTools/Source/C/Makefiles/compiler.makefile
>
> --
> 2.35.1
>
>
>
> 
>
>
>

-- 
Pedro Falcato

[-- Attachment #2: Type: text/html, Size: 1505 bytes --]

Re: [edk2-devel] [PATCH v3 0/3] BaseTools: fix gcc workaround

[Gerd Hoffmann]

On Mon, Apr 04, 2022 at 04:18:56PM +0100, Pedro Falcato wrote:
> Hi Gerd,
> 
> These patches are a great idea but I don't know if we can take GPLv2 code
> like that. Are they even mergeable into the main edk2 repo (as it's not
> compatible with BSD-2-clause)?

It's build system, doesn't end up being linked into firmware code, so
not sure license compatibility is actually a problem here.

In any case I strongly prefer to fix that in some automatic way which
does *not* require a new GCC12 tool chain definition.

So, any comments how to move forward with this?
Can we take the series as-is?
If not, other suggestions?
Second-best idea I've seen on the list is using 'gcc -dumpversion'.

Is it an option to just raise the minimum required gcc version to
something newer?  gcc5 was released almost 7 years ago ...

take care,
  Gerd

Re: [edk2-devel] [PATCH v3 0/3] BaseTools: fix gcc workaround

[Bob Feng]

Hi Gerd,

Your patches are great but I think we can't take them because of the incompatible license.
I think the new Toolchain definition, like GCC12, can not resolve this issue because Toolchain is not used for building BaseTools.
So I'd prefer the second option of using 'gcc -dumpversion'.

And also we have the task to convert the tools implemented by C to python implementation. After we have done that, there will be no BaseTools build issue.
https://github.com/tianocore/edk2-staging/tree/PyBaseTools

@Gao, Liming @Chen, Christine
Could you review the corresponding patch?

Thanks,
Bob

-----Original Message-----
From: Gerd Hoffmann <kraxel@redhat.com> 
Sent: Thursday, April 7, 2022 6:12 PM
To: Pedro Falcato <pedro.falcato@gmail.com>
Cc: edk2-devel-groups-io <devel@edk2.groups.io>; Chen, Christine <yuwei.chen@intel.com>; Gao, Liming <gaoliming@byosoft.com.cn>; Pawel Polawski <ppolawsk@redhat.com>; Feng, Bob C <bob.c.feng@intel.com>; Oliver Steffen <osteffen@redhat.com>; Rebecca Cran <rebecca@bsdio.com>
Subject: Re: [edk2-devel] [PATCH v3 0/3] BaseTools: fix gcc workaround

On Mon, Apr 04, 2022 at 04:18:56PM +0100, Pedro Falcato wrote:
> Hi Gerd,
> 
> These patches are a great idea but I don't know if we can take GPLv2 
> code like that. Are they even mergeable into the main edk2 repo (as 
> it's not compatible with BSD-2-clause)?

It's build system, doesn't end up being linked into firmware code, so not sure license compatibility is actually a problem here.

In any case I strongly prefer to fix that in some automatic way which does *not* require a new GCC12 tool chain definition.

So, any comments how to move forward with this?
Can we take the series as-is?
If not, other suggestions?
Second-best idea I've seen on the list is using 'gcc -dumpversion'.

Is it an option to just raise the minimum required gcc version to something newer?  gcc5 was released almost 7 years ago ...

take care,
  Gerd