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Array initialization with a non-array is expected to fail#131

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kroening merged 1 commit intodiffblue:masterfrom
tautschnig:struct-init-error
Aug 3, 2017
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Array initialization with a non-array is expected to fail#131
kroening merged 1 commit intodiffblue:masterfrom
tautschnig:struct-init-error

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@tautschnig tautschnig commented Jun 20, 2016

In the past, this failed an internal assertion; nowadays a proper error is
reported to the user. clang -Werror says:

Struct_Initialization1/main.c:9:38: error: suggest braces around initialization of subobject [-Werror,-Wmissing-braces]
struct _classinfo nullclass1 = { 42, 0, 0 };
                                     ^~~~
                                     {   }
1 error generated.

@tautschnig tautschnig mentioned this pull request Jun 20, 2016
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kroening commented Jun 20, 2016

My clang here (Apple LLVM version 7.3.0 (clang-703.0.31)) still eats it? What does the standard say?

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tautschnig commented Jun 20, 2016

@kroening Did you specify -Werror, or at least -Wall?

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kroening commented Jun 20, 2016

Yes!

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tautschnig commented Jun 20, 2016

Oh, sorry, it takes both -Wall and -Werror ... (which actually makes sense):

$ clang --version
Apple LLVM version 7.3.0 (clang-703.0.31)
Target: x86_64-apple-darwin15.5.0
Thread model: posix
InstalledDir: /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin
$ clang -Werror ansi-c/Struct_Initialization1/main.c
$ clang -Werror -Wall ansi-c/Struct_Initialization1/main.c
ansi-c/Struct_Initialization1/main.c:9:38: error: suggest braces around initialization of subobject [-Werror,-Wmissing-braces]
struct _classinfo nullclass1 = { 42, 0, 0 };
                                     ^~~~
                                     {   }
1 error generated.

@kroening kroening self-assigned this Jun 21, 2016
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kroening commented Jan 3, 2017

I.e., this is still a bug? Close the pull request?

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tautschnig commented Jan 3, 2017

This pull request would just change one "KNOWNBUG" to a proper "CORE" test as goto-cc produces the expected result. (At least I'd claim it is the expected result.)

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kroening commented Jan 3, 2017

Yes, but claim it's the wrong result!

@tautschnig tautschnig force-pushed the struct-init-error branch 2 times, most recently from 0703b4e to 20ecab6 Compare January 25, 2017 22:12
@forejtv forejtv assigned tautschnig and unassigned kroening Feb 20, 2017
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forejtv commented Feb 20, 2017

@tautschnig what is the status of this? Travis fails with Running Struct_Initialization1/test.desc [FAILED]

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tautschnig commented Feb 21, 2017

I had failed to parse @kroening last response on this PR. I'll have to take another look as to why this is now failing.

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tautschnig commented Feb 21, 2017

@forejtv @kroening I have adjusted the return-value check in test.desc (and also amended the commit message to include -Wall). So now we'd need to understand why @kroening does not like this one as proposed.

@tautschnig tautschnig assigned kroening and unassigned tautschnig Feb 21, 2017
@tautschnig tautschnig assigned tautschnig and unassigned kroening Mar 16, 2017
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kroening commented Apr 3, 2017

My suggestion would be to issue a warning instead of an error, just as gcc/clang do.

@tautschnig tautschnig force-pushed the struct-init-error branch from 93d1b8d to 14881e1 Compare June 8, 2017 08:56
@tautschnig tautschnig assigned kroening and unassigned tautschnig Jul 17, 2017
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tautschnig commented Jul 17, 2017

@kroening This is finally addressed following your suggestions. Review much appreciated.

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tautschnig commented Jul 17, 2017

It seems that #1111 is now getting urgent.

@tautschnig
Handle array initialization with a non-array gracefully
9740142 
clang -Wall says:

Struct_Initialization1/main.c:16:38: warning: suggest braces around initialization of subobject [-Wmissing-braces]
struct _classinfo nullclass1 = { 42, 1, 2, 3, 4 };
                                     ^~~~
                                     {   }
and then constructs a suitable object.

Our implementation now attempts to build an initializer list if a
variable-length array is encountered; if this succeeds, the same suitable object
is constructed. Variable-length arrays in the middle of a struct are not
permitted (neither by GCC nor Clang or our C front-end).
@kroening kroening merged commit 151efbc into diffblue:master Aug 3, 2017
@tautschnig tautschnig deleted the struct-init-error branch August 3, 2017 21:37
smowton pushed a commit to smowton/cbmc that referenced this pull request May 9, 2018
@NathanJPhillips @smowton
Merge pull request diffblue#131 from NathanJPhillips/cleanup/remove-g…
8ed81a6 
…et_invalid

Removed get_invalid
smowton pushed a commit to smowton/cbmc that referenced this pull request May 9, 2018
@marek-trtik
Merge pull request diffblue#131 from diffblue/marek/pch_forgotten_op_…
44c6b9b 
…less_PR

Added operator less for class argidx_and_tokennamet.
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@tautschnig @kroening @forejtv @peterschrammel