Fixed issue #128882: don't warn if 1st argument to 'getcwd' is NULL

Author: seanm

clang/lib/StaticAnalyzer/Checkers/StdLibraryFunctionsChecker.cpp

@@ -2663,7 +2663,6 @@ void StdLibraryFunctionsChecker::initFunctionSummaries(
             .Case({ArgumentCondition(1, WithinRange, Range(1, SizeMax)),
                    IsNull(Ret)},
                   ErrnoNEZeroIrrelevant, GenericFailureMsg)
-            .ArgConstraint(NotNull(ArgNo(0)))
             .ArgConstraint(
                 BufferSize(/*Buffer*/ ArgNo(0), /*BufSize*/ ArgNo(1)))
             .ArgConstraint(

clang/test/Analysis/errno-stdlibraryfunctions.c

@@ -105,9 +105,6 @@ void errno_getcwd(char *Buf, size_t Sz) {
     clang_analyzer_eval(errno != 0);   // expected-warning{{TRUE}}
     clang_analyzer_eval(Path == NULL); // expected-warning{{TRUE}}
     if (errno) {}                      // no warning
-  } else if (Path == NULL) {
-    clang_analyzer_eval(errno != 0);   // expected-warning{{TRUE}}
-    if (errno) {}                      // no warning
   } else {
     clang_analyzer_eval(Path == Buf);  // expected-warning{{TRUE}}
     if (errno) {}                      // expected-warning{{An undefined value may be read from 'errno'}}