Resolve or silence some warnings (#1905)

* Resolve some warnings

- Their frequent appearance in the build logs is driving me nuts

* Silence warnings about `offsetof`

* Don't apply `-Wno-invalid-offset` to C, only to C++

6 files changed, 40 insertions, 29 deletions

diff --git a/src/ARMJIT_A64/ARMJIT_Compiler.h b/src/ARMJIT_A64/ARMJIT_Compiler.h
index 04f12e8..2b0048a 100644
--- a/src/ARMJIT_A64/ARMJIT_Compiler.h
+++ b/src/ARMJIT_A64/ARMJIT_Compiler.h
@@ -69,7 +69,7 @@ struct Op2
     bool IsSimpleReg()
     { return !IsImm && !Reg.ShiftAmount && Reg.ShiftType == Arm64Gen::ST_LSL; }
     bool ImmFits12Bit()
-    { return IsImm && (Imm & 0xFFF == Imm); }
+    { return IsImm && ((Imm & 0xFFF) == Imm); }
     bool IsZero()
     { return IsImm && !Imm; }
 
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index b1ae4c4..afabc03 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -128,6 +128,15 @@ add_subdirectory(teakra EXCLUDE_FROM_ALL)
 target_compile_options(teakra PRIVATE "$<$<CONFIG:DEBUG>:-Og>")
 target_link_libraries(core PRIVATE teakra)
 
+if (NOT MSVC)
+    # MSVC has its own compiler flag syntax; if we ever support it,
+    # be sure to silence any equivalent warnings there.
+
+    target_compile_options(core PRIVATE "$<$<COMPILE_LANGUAGE:CXX>:-Wno-invalid-offsetof>")
+    # These warnings are excessive, and are only triggered in the ARMJIT code
+    # (which is fundamentally non-portable, so this is fine)
+endif()
+
 find_library(m MATH_LIBRARY)
 
 if (MATH_LIBRARY)
diff --git a/src/GPU3D_OpenGL.cpp b/src/GPU3D_OpenGL.cpp
index 27711a8..3e9ce5b 100644
--- a/src/GPU3D_OpenGL.cpp
+++ b/src/GPU3D_OpenGL.cpp
@@ -31,7 +31,7 @@ namespace melonDS
 bool GLRenderer::BuildRenderShader(u32 flags, const char* vs, const char* fs)
 {
     char shadername[32];
-    sprintf(shadername, "RenderShader%02X", flags);
+    snprintf(shadername, sizeof(shadername), "RenderShader%02X", flags);
 
     int headerlen = strlen(kShaderHeader);
 
diff --git a/src/GPU3D_Soft.h b/src/GPU3D_Soft.h
index 8fb4201..de65944 100644
--- a/src/GPU3D_Soft.h
+++ b/src/GPU3D_Soft.h
@@ -178,7 +178,7 @@ private:
             {
                 // Z-buffering: linear interpolation
                 // still doesn't quite match hardware...
-                s32 base, disp, factor;
+                s32 base = 0, disp = 0, factor = 0;
 
                 if (z0 < z1)
                 {
@@ -337,7 +337,7 @@ private:
 
         constexpr s32 XVal() const
         {
-            s32 ret;
+            s32 ret = 0;
             if (Negative) ret = x0 - (dx >> 18);
             else          ret = x0 + (dx >> 18);
 
diff --git a/src/NDS.cpp b/src/NDS.cpp
index 7c176fa..1d7e34a 100644
--- a/src/NDS.cpp
+++ b/src/NDS.cpp
@@ -1497,40 +1497,40 @@ void NDS::NocashPrint(u32 ncpu, u32 addr)
 
             if (cmd[0] == 'r')
             {
-                if      (!strcmp(cmd, "r0")) sprintf(subs, "%08X", cpu->R[0]);
-                else if (!strcmp(cmd, "r1")) sprintf(subs, "%08X", cpu->R[1]);
-                else if (!strcmp(cmd, "r2")) sprintf(subs, "%08X", cpu->R[2]);
-                else if (!strcmp(cmd, "r3")) sprintf(subs, "%08X", cpu->R[3]);
-                else if (!strcmp(cmd, "r4")) sprintf(subs, "%08X", cpu->R[4]);
-                else if (!strcmp(cmd, "r5")) sprintf(subs, "%08X", cpu->R[5]);
-                else if (!strcmp(cmd, "r6")) sprintf(subs, "%08X", cpu->R[6]);
-                else if (!strcmp(cmd, "r7")) sprintf(subs, "%08X", cpu->R[7]);
-                else if (!strcmp(cmd, "r8")) sprintf(subs, "%08X", cpu->R[8]);
-                else if (!strcmp(cmd, "r9")) sprintf(subs, "%08X", cpu->R[9]);
-                else if (!strcmp(cmd, "r10")) sprintf(subs, "%08X", cpu->R[10]);
-                else if (!strcmp(cmd, "r11")) sprintf(subs, "%08X", cpu->R[11]);
-                else if (!strcmp(cmd, "r12")) sprintf(subs, "%08X", cpu->R[12]);
-                else if (!strcmp(cmd, "r13")) sprintf(subs, "%08X", cpu->R[13]);
-                else if (!strcmp(cmd, "r14")) sprintf(subs, "%08X", cpu->R[14]);
-                else if (!strcmp(cmd, "r15")) sprintf(subs, "%08X", cpu->R[15]);
+                if      (!strcmp(cmd, "r0")) snprintf(subs, sizeof(subs), "%08X", cpu->R[0]);
+                else if (!strcmp(cmd, "r1")) snprintf(subs, sizeof(subs), "%08X", cpu->R[1]);
+                else if (!strcmp(cmd, "r2")) snprintf(subs, sizeof(subs), "%08X", cpu->R[2]);
+                else if (!strcmp(cmd, "r3")) snprintf(subs, sizeof(subs), "%08X", cpu->R[3]);
+                else if (!strcmp(cmd, "r4")) snprintf(subs, sizeof(subs), "%08X", cpu->R[4]);
+                else if (!strcmp(cmd, "r5")) snprintf(subs, sizeof(subs), "%08X", cpu->R[5]);
+                else if (!strcmp(cmd, "r6")) snprintf(subs, sizeof(subs), "%08X", cpu->R[6]);
+                else if (!strcmp(cmd, "r7")) snprintf(subs, sizeof(subs), "%08X", cpu->R[7]);
+                else if (!strcmp(cmd, "r8")) snprintf(subs, sizeof(subs), "%08X", cpu->R[8]);
+                else if (!strcmp(cmd, "r9")) snprintf(subs, sizeof(subs), "%08X", cpu->R[9]);
+                else if (!strcmp(cmd, "r10")) snprintf(subs, sizeof(subs), "%08X", cpu->R[10]);
+                else if (!strcmp(cmd, "r11")) snprintf(subs, sizeof(subs), "%08X", cpu->R[11]);
+                else if (!strcmp(cmd, "r12")) snprintf(subs, sizeof(subs), "%08X", cpu->R[12]);
+                else if (!strcmp(cmd, "r13")) snprintf(subs, sizeof(subs), "%08X", cpu->R[13]);
+                else if (!strcmp(cmd, "r14")) snprintf(subs, sizeof(subs), "%08X", cpu->R[14]);
+                else if (!strcmp(cmd, "r15")) snprintf(subs, sizeof(subs), "%08X", cpu->R[15]);
             }
             else
             {
-                if      (!strcmp(cmd, "sp")) sprintf(subs, "%08X", cpu->R[13]);
-                else if (!strcmp(cmd, "lr")) sprintf(subs, "%08X", cpu->R[14]);
-                else if (!strcmp(cmd, "pc")) sprintf(subs, "%08X", cpu->R[15]);
-                else if (!strcmp(cmd, "frame")) sprintf(subs, "%u", NumFrames);
-                else if (!strcmp(cmd, "scanline")) sprintf(subs, "%u", GPU.VCount);
-                else if (!strcmp(cmd, "totalclks")) sprintf(subs, "%" PRIu64, GetSysClockCycles(0));
-                else if (!strcmp(cmd, "lastclks")) sprintf(subs, "%" PRIu64, GetSysClockCycles(1));
+                if      (!strcmp(cmd, "sp")) snprintf(subs, sizeof(subs), "%08X", cpu->R[13]);
+                else if (!strcmp(cmd, "lr")) snprintf(subs, sizeof(subs), "%08X", cpu->R[14]);
+                else if (!strcmp(cmd, "pc")) snprintf(subs, sizeof(subs), "%08X", cpu->R[15]);
+                else if (!strcmp(cmd, "frame")) snprintf(subs, sizeof(subs), "%u", NumFrames);
+                else if (!strcmp(cmd, "scanline")) snprintf(subs, sizeof(subs), "%u", GPU.VCount);
+                else if (!strcmp(cmd, "totalclks")) snprintf(subs, sizeof(subs), "%" PRIu64, GetSysClockCycles(0));
+                else if (!strcmp(cmd, "lastclks")) snprintf(subs, sizeof(subs), "%" PRIu64, GetSysClockCycles(1));
                 else if (!strcmp(cmd, "zeroclks"))
                 {
-                    sprintf(subs, "%s", "");
+                    snprintf(subs, sizeof(subs), "%s", "");
                     GetSysClockCycles(1);
                 }
             }
 
-            int slen = strlen(subs);
+            int slen = strnlen(subs, sizeof(subs));
             if ((ptr+slen) > 1023) slen = 1023-ptr;
             strncpy(&output[ptr], subs, slen);
             ptr += slen;
diff --git a/src/SPU.cpp b/src/SPU.cpp
index f0d5946..8630709 100644
--- a/src/SPU.cpp
+++ b/src/SPU.cpp
@@ -621,6 +621,8 @@ s32 SPUChannel::Run()
                    (PrevSample[0] * InterpCubic[samplepos][2]) +
                    (val           * InterpCubic[samplepos][3])) >> 14;
             break;
+        default:
+            break;
         }
     }