Bug Summary

File:clang/lib/Driver/ToolChains/MSP430.cpp
Warning:line 104, column 12
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name MSP430.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -relaxed-aliasing -fmath-errno -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210926122410+d23fd8ae8906/build-llvm -resource-dir /usr/lib/llvm-14/lib/clang/14.0.0 -D CLANG_ROUND_TRIP_CC1_ARGS=ON -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I tools/clang/lib/Driver -I /build/llvm-toolchain-snapshot-14~++20210926122410+d23fd8ae8906/clang/lib/Driver -I /build/llvm-toolchain-snapshot-14~++20210926122410+d23fd8ae8906/clang/include -I tools/clang/include -I include -I /build/llvm-toolchain-snapshot-14~++20210926122410+d23fd8ae8906/llvm/include -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-14/lib/clang/14.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-command-line-argument -Wno-unknown-warning-option -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-14~++20210926122410+d23fd8ae8906/build-llvm -ferror-limit 19 -fvisibility-inlines-hidden -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2021-09-26-234817-15343-1 -x c++ /build/llvm-toolchain-snapshot-14~++20210926122410+d23fd8ae8906/clang/lib/Driver/ToolChains/MSP430.cpp
1//===--- MSP430.cpp - MSP430 Helpers for Tools ------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "MSP430.h"
10#include "CommonArgs.h"
11#include "Gnu.h"
12#include "clang/Driver/Compilation.h"
13#include "clang/Driver/InputInfo.h"
14#include "clang/Driver/Multilib.h"
15#include "clang/Driver/Options.h"
16#include "llvm/Option/ArgList.h"
17#include "llvm/Support/FileSystem.h"
18#include "llvm/Support/Path.h"
19
20using namespace clang::driver;
21using namespace clang::driver::toolchains;
22using namespace clang::driver::tools;
23using namespace clang;
24using namespace llvm::opt;
25
26static bool isSupportedMCU(const StringRef MCU) {
27 return llvm::StringSwitch<bool>(MCU)
28#define MSP430_MCU(NAME) .Case(NAME, true)
29#include "clang/Basic/MSP430Target.def"
30 .Default(false);
31}
32
33static StringRef getSupportedHWMult(const Arg *MCU) {
34 if (!MCU)
35 return "none";
36
37 return llvm::StringSwitch<StringRef>(MCU->getValue())
38#define MSP430_MCU_FEAT(NAME, HWMULT) .Case(NAME, HWMULT)
39#include "clang/Basic/MSP430Target.def"
40 .Default("none");
41}
42
43static StringRef getHWMultLib(const ArgList &Args) {
44 StringRef HWMult = Args.getLastArgValue(options::OPT_mhwmult_EQ, "auto");
45 if (HWMult == "auto") {
46 HWMult = getSupportedHWMult(Args.getLastArg(options::OPT_mmcu_EQ));
47 }
48
49 return llvm::StringSwitch<StringRef>(HWMult)
50 .Case("16bit", "-lmul_16")
51 .Case("32bit", "-lmul_32")
52 .Case("f5series", "-lmul_f5")
53 .Default("-lmul_none");
54}
55
56void msp430::getMSP430TargetFeatures(const Driver &D, const ArgList &Args,
57 std::vector<StringRef> &Features) {
58 const Arg *MCU = Args.getLastArg(options::OPT_mmcu_EQ);
59 if (MCU && !isSupportedMCU(MCU->getValue())) {
1
Assuming 'MCU' is non-null
2
Taking false branch
60 D.Diag(diag::err_drv_clang_unsupported) << MCU->getValue();
61 return;
62 }
63
64 const Arg *HWMultArg = Args.getLastArg(options::OPT_mhwmult_EQ);
3
'HWMultArg' initialized here
65 if (!MCU
3.1
'MCU' is non-null
&& !HWMultArg)
66 return;
67
68 StringRef HWMult = HWMultArg ? HWMultArg->getValue() : "auto";
4
Assuming 'HWMultArg' is null
5
'?' condition is false
69 StringRef SupportedHWMult = getSupportedHWMult(MCU);
70
71 if (HWMult == "auto") {
6
Assuming the condition is false
7
Taking false branch
72 // 'auto' - deduce hw multiplier support based on mcu name provided.
73 // If no mcu name is provided, assume no hw multiplier is supported.
74 if (!MCU)
75 D.Diag(clang::diag::warn_drv_msp430_hwmult_no_device);
76 HWMult = SupportedHWMult;
77 }
78
79 if (HWMult == "none") {
8
Assuming the condition is false
80 // 'none' - disable hw multiplier.
81 Features.push_back("-hwmult16");
82 Features.push_back("-hwmult32");
83 Features.push_back("-hwmultf5");
84 return;
85 }
86
87 if (MCU
8.1
'MCU' is non-null
&& SupportedHWMult == "none")
9
Assuming the condition is false
88 D.Diag(clang::diag::warn_drv_msp430_hwmult_unsupported) << HWMult;
89 if (MCU
9.1
'MCU' is non-null
&& HWMult != SupportedHWMult)
10
Taking false branch
90 D.Diag(clang::diag::warn_drv_msp430_hwmult_mismatch)
91 << SupportedHWMult << HWMult;
92
93 if (HWMult == "16bit") {
11
Assuming the condition is false
12
Taking false branch
94 // '16bit' - for 16-bit only hw multiplier.
95 Features.push_back("+hwmult16");
96 } else if (HWMult == "32bit") {
13
Assuming the condition is false
14
Taking false branch
97 // '32bit' - for 16/32-bit hw multiplier.
98 Features.push_back("+hwmult32");
99 } else if (HWMult == "f5series") {
15
Assuming the condition is false
16
Taking false branch
100 // 'f5series' - for 16/32-bit hw multiplier supported by F5 series mcus.
101 Features.push_back("+hwmultf5");
102 } else {
103 D.Diag(clang::diag::err_drv_unsupported_option_argument)
104 << HWMultArg->getAsString(Args) << HWMult;
17
Called C++ object pointer is null
105 }
106}
107
108/// MSP430 Toolchain
109MSP430ToolChain::MSP430ToolChain(const Driver &D, const llvm::Triple &Triple,
110 const ArgList &Args)
111 : Generic_ELF(D, Triple, Args) {
112
113 StringRef MultilibSuf = "";
114
115 GCCInstallation.init(Triple, Args);
116 if (GCCInstallation.isValid()) {
117 MultilibSuf = GCCInstallation.getMultilib().gccSuffix();
118
119 SmallString<128> GCCBinPath;
120 llvm::sys::path::append(GCCBinPath,
121 GCCInstallation.getParentLibPath(), "..", "bin");
122 addPathIfExists(D, GCCBinPath, getProgramPaths());
123
124 SmallString<128> GCCRtPath;
125 llvm::sys::path::append(GCCRtPath,
126 GCCInstallation.getInstallPath(), MultilibSuf);
127 addPathIfExists(D, GCCRtPath, getFilePaths());
128 }
129
130 SmallString<128> SysRootDir(computeSysRoot());
131 llvm::sys::path::append(SysRootDir, "msp430-elf", "lib", MultilibSuf);
132 addPathIfExists(D, SysRootDir, getFilePaths());
133}
134
135std::string MSP430ToolChain::computeSysRoot() const {
136 if (!getDriver().SysRoot.empty())
137 return getDriver().SysRoot;
138
139 SmallString<128> Dir;
140 if (GCCInstallation.isValid())
141 llvm::sys::path::append(Dir, GCCInstallation.getParentLibPath(), "..");
142 else
143 llvm::sys::path::append(Dir, getDriver().Dir, "..");
144
145 return std::string(Dir.str());
146}
147
148void MSP430ToolChain::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
149 ArgStringList &CC1Args) const {
150 if (DriverArgs.hasArg(options::OPT_nostdinc) ||
151 DriverArgs.hasArg(options::OPT_nostdlibinc))
152 return;
153
154 SmallString<128> Dir(computeSysRoot());
155 llvm::sys::path::append(Dir, "msp430-elf", "include");
156 addSystemInclude(DriverArgs, CC1Args, Dir.str());
157}
158
159void MSP430ToolChain::addClangTargetOptions(const ArgList &DriverArgs,
160 ArgStringList &CC1Args,
161 Action::OffloadKind) const {
162 CC1Args.push_back("-nostdsysteminc");
163
164 const auto *MCUArg = DriverArgs.getLastArg(options::OPT_mmcu_EQ);
165 if (!MCUArg)
166 return;
167
168 const StringRef MCU = MCUArg->getValue();
169 if (MCU.startswith("msp430i")) {
170 // 'i' should be in lower case as it's defined in TI MSP430-GCC headers
171 CC1Args.push_back(DriverArgs.MakeArgString(
172 "-D__MSP430i" + MCU.drop_front(7).upper() + "__"));
173 } else {
174 CC1Args.push_back(DriverArgs.MakeArgString("-D__" + MCU.upper() + "__"));
175 }
176}
177
178Tool *MSP430ToolChain::buildLinker() const {
179 return new tools::msp430::Linker(*this);
180}
181
182void msp430::Linker::AddStartFiles(bool UseExceptions, const ArgList &Args,
183 ArgStringList &CmdArgs) const {
184 const ToolChain &ToolChain = getToolChain();
185
186 CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath("crt0.o")));
187 const char *crtbegin = UseExceptions ? "crtbegin.o" : "crtbegin_no_eh.o";
188 CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crtbegin)));
189}
190
191void msp430::Linker::AddDefaultLibs(const llvm::opt::ArgList &Args,
192 llvm::opt::ArgStringList &CmdArgs) const {
193 const ToolChain &ToolChain = getToolChain();
194 const Driver &D = ToolChain.getDriver();
195
196 CmdArgs.push_back("--start-group");
197 CmdArgs.push_back(Args.MakeArgString(getHWMultLib(Args)));
198 CmdArgs.push_back("-lc");
199 AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
200 CmdArgs.push_back("-lcrt");
201
202 if (Args.hasArg(options::OPT_msim)) {
203 CmdArgs.push_back("-lsim");
204
205 // msp430-sim.ld relies on __crt0_call_exit being implicitly .refsym-ed
206 // in main() by msp430-gcc.
207 // This workaround should work seamlessly unless the compilation unit that
208 // contains main() is compiled by clang and then passed to
209 // gcc compiler driver for linkage.
210 CmdArgs.push_back("--undefined=__crt0_call_exit");
211 } else
212 CmdArgs.push_back("-lnosys");
213
214 CmdArgs.push_back("--end-group");
215 AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
216}
217
218void msp430::Linker::AddEndFiles(bool UseExceptions, const ArgList &Args,
219 ArgStringList &CmdArgs) const {
220 const ToolChain &ToolChain = getToolChain();
221 const Driver &D = ToolChain.getDriver();
222
223 const char *crtend = UseExceptions ? "crtend.o" : "crtend_no_eh.o";
224 CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(crtend)));
225 AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
226}
227
228static void AddSspArgs(const ArgList &Args, ArgStringList &CmdArgs) {
229 Arg *SspFlag = Args.getLastArg(
230 options::OPT_fno_stack_protector, options::OPT_fstack_protector,
231 options::OPT_fstack_protector_all, options::OPT_fstack_protector_strong);
232
233 if (SspFlag &&
234 !SspFlag->getOption().matches(options::OPT_fno_stack_protector)) {
235 CmdArgs.push_back("-lssp_nonshared");
236 CmdArgs.push_back("-lssp");
237 }
238}
239
240static void AddImplicitLinkerScript(const std::string SysRoot,
241 const ArgList &Args,
242 ArgStringList &CmdArgs) {
243 if (Args.hasArg(options::OPT_T))
244 return;
245
246 if (Args.hasArg(options::OPT_msim)) {
247 CmdArgs.push_back("-Tmsp430-sim.ld");
248 return;
249 }
250
251 const Arg *MCUArg = Args.getLastArg(options::OPT_mmcu_EQ);
252 if (!MCUArg)
253 return;
254
255 SmallString<128> MCULinkerScriptPath(SysRoot);
256 llvm::sys::path::append(MCULinkerScriptPath, "include");
257 // -L because <mcu>.ld INCLUDEs <mcu>_symbols.ld
258 CmdArgs.push_back(Args.MakeArgString("-L" + MCULinkerScriptPath));
259 CmdArgs.push_back(
260 Args.MakeArgString("-T" + StringRef(MCUArg->getValue()) + ".ld"));
261}
262
263void msp430::Linker::ConstructJob(Compilation &C, const JobAction &JA,
264 const InputInfo &Output,
265 const InputInfoList &Inputs,
266 const ArgList &Args,
267 const char *LinkingOutput) const {
268 const ToolChain &ToolChain = getToolChain();
269 const Driver &D = ToolChain.getDriver();
270 std::string Linker = ToolChain.GetProgramPath(getShortName());
271 ArgStringList CmdArgs;
272 bool UseExceptions = Args.hasFlag(options::OPT_fexceptions,
273 options::OPT_fno_exceptions, false);
274 bool UseStartAndEndFiles = !Args.hasArg(options::OPT_nostdlib, options::OPT_r,
275 options::OPT_nostartfiles);
276
277 if (Args.hasArg(options::OPT_mrelax))
278 CmdArgs.push_back("--relax");
279 if (!Args.hasArg(options::OPT_r, options::OPT_g_Group))
280 CmdArgs.push_back("--gc-sections");
281
282 Args.AddAllArgs(CmdArgs, {
283 options::OPT_e,
284 options::OPT_n,
285 options::OPT_s,
286 options::OPT_t,
287 options::OPT_u,
288 });
289
290 if (UseStartAndEndFiles)
291 AddStartFiles(UseExceptions, Args, CmdArgs);
292
293 Args.AddAllArgs(CmdArgs, options::OPT_L);
294 ToolChain.AddFilePathLibArgs(Args, CmdArgs);
295 AddLinkerInputs(getToolChain(), Inputs, Args, CmdArgs, JA);
296
297 if (!Args.hasArg(options::OPT_nostdlib, options::OPT_r,
298 options::OPT_nodefaultlibs)) {
299 AddSspArgs(Args, CmdArgs);
300 AddRunTimeLibs(ToolChain, D, CmdArgs, Args);
301 if (!Args.hasArg(options::OPT_nolibc)) {
302 AddDefaultLibs(Args, CmdArgs);
303 AddImplicitLinkerScript(D.SysRoot, Args, CmdArgs);
304 }
305 }
306
307 if (UseStartAndEndFiles)
308 AddEndFiles(UseExceptions, Args, CmdArgs);
309
310 CmdArgs.push_back("-o");
311 CmdArgs.push_back(Output.getFilename());
312
313 Args.AddAllArgs(CmdArgs, options::OPT_T);
314
315 C.addCommand(std::make_unique<Command>(
316 JA, *this, ResponseFileSupport::AtFileCurCP(), Args.MakeArgString(Linker),
317 CmdArgs, Inputs, Output));
318}