Add -Wno-implicit-function-declaration to a few places to work w D122983

[erichkeane]

Summary

D122983 intends to make these cases a 'warning as error' in C11 and C17
modes, and an attempt to set these to C99 mode caused more failures due
to included-files no longer containing certain symbols. This patch just
adds the warning-opt-out to the tests that matter. See
https://reviews.llvm.org/D122983 for details.

[aaron.ballman]

LGTM aside from the question I asked. FWIW, this is an NFC change as it only disables warnings that we know are triggered.

SingleSource/Regression/C/gcc-c-torture/execute/CMakeLists.txt

4

Should the new flag be within quotes like -w or does this not matter? (I don't know Cmake well enough to know.)

[erichkeane]

SingleSource/Regression/C/gcc-c-torture/execute/CMakeLists.txt

4

I have no idea, I was following what the rest of the entries in this list ended up doing (I think this was the last I found). I suspect it doesn't matter.

[cor3ntin]

SingleSource/Regression/C/gcc-c-torture/execute/CMakeLists.txt

4

It doesn't, in the absence of spaces/semicolon, both are fine

[Meinersbur]

@cor3ntin is correct. For consistency could you also remove the quotes around -w?

However, what use is the change, -w already disables all warnings? https://reviews.llvm.org/D122983#3426261 seems to summarize the effect of D122983, but doesn't -w still override "Warn-as-default-error"?

[aaron.ballman]

In D123241#3434530, @Meinersbur wrote:

@cor3ntin is correct. For consistency could you also remove the quotes around -w?

+1, probably a good idea so no one else gets confused like I did.

However, what use is the change, -w already disables all warnings? https://reviews.llvm.org/D122983#3426261 seems to summarize the effect of D122983, but doesn't -w still override "Warn-as-default-error"?

-w doesn't override warn-defaults-as-error: https://godbolt.org/z/8rKGh366h

[erichkeane]

Quote around "-w" removed! If this is OK, how do I commit? I've never committed to this repo before, is it hte same permission set as normal llvm?

[erichkeane]

Turns out I just have push rights! So, done! Phab won't let me edit related commits, but the commit that merged was: a87f4e4f9808a397dc4c575013142c9eac0b7eba

[zibi]

I'm seeing this error:

MultiSource/Benchmarks/Prolangs-C/bison/symtab.c:65:3: error: call to undeclared library function 'strcpy' with type 'char *(char *, const char *)'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
  strcpy(result, s);
  ^

Have you missed MultiSource/Benchmarks/Prolangs-C/bison/CMakeLists.txt to turn off the warning?

[zibi]

In D123241#3463076, @zibi wrote:

Have you missed MultiSource/Benchmarks/Prolangs-C/bison/CMakeLists.txt to turn off the warning?

@erichkeane Erich, will you be able to provide the fix for this? Please let me know ETA so I can plan accordingly.

[zibi]

In D123241#3463208, @zibi wrote:

In D123241#3463076, @zibi wrote:

Have you missed MultiSource/Benchmarks/Prolangs-C/bison/CMakeLists.txt to turn off the warning?

@erichkeane Erich, will you be able to provide the fix for this? Please let me know ETA so I can plan accordingly.

@aaron.ballman Thank you for the quick fix. It addressed my concern.

MultiSource/Applications/siod/CMakeLists.txt

-list(APPEND CPPFLAGS -D__USE_MISC -D__USE_GNU -D__USE_SVID -D__USE_XOPEN_EXTENDED -D__USE_XOPEN -Dunix)
+list(APPEND CPPFLAGS -D__USE_MISC -D__USE_GNU -D__USE_SVID -D__USE_XOPEN_EXTENDED -D__USE_XOPEN -Dunix -Wno-implicit-function-declaration)
 list(APPEND LDFLAGS -lm)
 set(RUN_OPTIONS -v1 test.scm)
 llvm_multisource(siod)
 llvm_test_data(siod test.scm)

MultiSource/Benchmarks/MiBench/office-ispell/CMakeLists.txt

-list(APPEND CPPFLAGS -Dconst=)
+list(APPEND CPPFLAGS  -Wno-implicit-function-declaration -Dconst=)
 list(APPEND LDFLAGS -lm)
 set(RUN_OPTIONS -a -d americanmed+ < large.txt)
 llvm_multisource(office-ispell)
 llvm_test_data(office-ispell americanmed+.hash large.txt)

MultiSource/Benchmarks/Prolangs-C/archie-client/CMakeLists.txt

 include(CheckFunctionExists)
+list(APPEND CPPFLAGS -Wno-implicit-function-declaration)
 check_function_exists(re_comp HAVE_RE_COMP)
 
 if(HAVE_RE_COMP)
   if(TARGET_OS STREQUAL "SunOS")
     list(APPEND LDFLAGS -lsocket -lnsl)
   endif()
   llvm_multisource(archie)
   target_include_directories(archie PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
 endif()

MultiSource/Benchmarks/Prolangs-C/plot2fig/CMakeLists.txt

 include(CheckFunctionExists)
 check_function_exists(re_comp HAVE_RE_COMP)
+list(APPEND CPPFLAGS -Wno-implicit-function-declaration)
 if(HAVE_RE_COMP)
   list(APPEND LDFLAGS -lm)
   llvm_multisource(plot2fig)
 endif()

SingleSource/Regression/C/gcc-c-torture/execute/CMakeLists.txt

 add_subdirectory(ieee)
 
 # GCC C Torture Suite is conventionally run without warnings
-list(APPEND CFLAGS "-w")
+list(APPEND CFLAGS  -Wno-implicit-function-declaration -w)
 
 set(TestsToSkip)
 
 ##
 ## Main Test Blacklist for Clang
 ##
 
 # Tests with features unsupported by Clang (usually GCC extensions)