[PATCH 2/3] BaseTools GCC5: disable warnings-as-errors for now

[Ard Biesheuvel <ard.biesheuvel@linaro.org>]

GCC5 runs in LTO mode, which means it may generate code from an
intermediate representation during the link stage, at which time
additional diagnostics are run that may emit warnings.

Some of these warnings seem to be spurious, e.g., the following
warning which is emitted when building OVMF for IA32 or ArmVirtQemu
for ARM (but not for X64 resp. AARCH64)

  .../MdeModulePkg/Library/UefiHiiLib/HiiLib.c:
                 In function 'HiiCreateGuidOpCode.constprop':
  .../MdeModulePkg/Library/UefiHiiLib/HiiLib.c:3228:10:
                 error: function may return address of local variable
                                            [-Werror=return-local-addr]
     return (UINT8 *)OpCodePointer;
            ^
  .../MdeModulePkg/Library/UefiHiiLib/HiiLib.c:3208:17: note: declared here
     EFI_IFR_GUID  OpCode;
                   ^
  lto1: all warnings being treated as errors
  lto-wrapper: fatal error: gcc returned 1 exit status

So before adding the contents of CC_FLAGS to the linker command line,
defuse the default '-Werror' by adding '-Wno-error' to DLINK2_FLAGS
for GCC5.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---
 BaseTools/Conf/tools_def.template | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/BaseTools/Conf/tools_def.template b/BaseTools/Conf/tools_def.template
index 289e75cc3be6..1f55740929d7 100644
--- a/BaseTools/Conf/tools_def.template
+++ b/BaseTools/Conf/tools_def.template
@@ -4466,9 +4466,9 @@ DEFINE GCC5_X64_CC_FLAGS             = DEF(GCC49_X64_CC_FLAGS) -flto -fno-builti
 DEFINE GCC5_IA32_X64_DLINK_COMMON    = DEF(GCC49_IA32_X64_DLINK_COMMON)
 DEFINE GCC5_IA32_X64_ASLDLINK_FLAGS  = DEF(GCC49_IA32_X64_ASLDLINK_FLAGS)
 DEFINE GCC5_IA32_X64_DLINK_FLAGS     = DEF(GCC49_IA32_X64_DLINK_FLAGS) -flto
-DEFINE GCC5_IA32_DLINK2_FLAGS        = DEF(GCC49_IA32_DLINK2_FLAGS)
+DEFINE GCC5_IA32_DLINK2_FLAGS        = DEF(GCC49_IA32_DLINK2_FLAGS) -Wno-error
 DEFINE GCC5_X64_DLINK_FLAGS          = DEF(GCC49_X64_DLINK_FLAGS) -flto
-DEFINE GCC5_X64_DLINK2_FLAGS         = DEF(GCC49_X64_DLINK2_FLAGS)
+DEFINE GCC5_X64_DLINK2_FLAGS         = DEF(GCC49_X64_DLINK2_FLAGS) -Wno-error
 DEFINE GCC5_ASM_FLAGS                = DEF(GCC49_ASM_FLAGS)
 DEFINE GCC5_ARM_ASM_FLAGS            = DEF(GCC49_ARM_ASM_FLAGS)
 DEFINE GCC5_AARCH64_ASM_FLAGS        = DEF(GCC49_AARCH64_ASM_FLAGS)
@@ -4476,9 +4476,9 @@ DEFINE GCC5_ARM_CC_FLAGS             = DEF(GCC49_ARM_CC_FLAGS)
 DEFINE GCC5_AARCH64_CC_FLAGS         = DEF(GCC49_AARCH64_CC_FLAGS)
 DEFINE GCC5_AARCH64_CC_XIPFLAGS      = DEF(GCC49_AARCH64_CC_XIPFLAGS)
 DEFINE GCC5_ARM_DLINK_FLAGS          = DEF(GCC49_ARM_DLINK_FLAGS)
-DEFINE GCC5_ARM_DLINK2_FLAGS         = DEF(GCC49_ARM_DLINK2_FLAGS)
+DEFINE GCC5_ARM_DLINK2_FLAGS         = DEF(GCC49_ARM_DLINK2_FLAGS) -Wno-error
 DEFINE GCC5_AARCH64_DLINK_FLAGS      = DEF(GCC49_AARCH64_DLINK_FLAGS)
-DEFINE GCC5_AARCH64_DLINK2_FLAGS     = DEF(GCC49_AARCH64_DLINK2_FLAGS)
+DEFINE GCC5_AARCH64_DLINK2_FLAGS     = DEF(GCC49_AARCH64_DLINK2_FLAGS) -Wno-error
 DEFINE GCC5_ARM_ASLDLINK_FLAGS       = DEF(GCC49_ARM_ASLDLINK_FLAGS)
 DEFINE GCC5_AARCH64_ASLDLINK_FLAGS   = DEF(GCC49_AARCH64_ASLDLINK_FLAGS)
 
-- 
2.7.4